Tfl 435 
.N5 
Copy 1 



loT* 



NOTES ON CEHENT TESTING 

in addition to those submitted 
May 24, 1900. 

ALSO 

ANSWERING REPORT 

To one made March 5, 1901, 

BY THE 

ENGINEER OF THE DEPARTMENT OF HIGHWAYS, 

Borough of Brooklyn. 

On Violation of Specifications for Concrete Street Foundations. 



REPORT 



OF THE 



COMMISSIONERS OF ACCOUNTS 



OF 



The City of new York. 



HAY 20, 1901 



NOTES ON CEHENT TESTING 

in addition to tliose submitted 
May 24, 1900. 

ALSO 

ANSWERING REPORT 

OF THE COMMISSIONERS OF ACCOUNTS 

To one made March 5, 1901, 

BY THE 

Engineer of the Department of Highways, 

Borough of Brooklyn, 

On Violation of Specifications for Concrete Street Foundations. 



REPORT 



TO THE 



Hon. ROBERT A. VAN WYCK, Mayor, 

MADE BY 

JOHN C. HERTLE, 

EDWARD OWEN, 

Commissioners of Accounts of The City of New York, 

riAY 20, 1901. 



NEW YORK : 
Martin B. Brown Co., Printers and Stationers, 

NOS. 49 to 57 PARK place. 



rgoi. 



^ 



^H^ 
4"^ 



AUG 7 ">07 



TABLE OF CONTENTS, 

Showing Subdivision of Reports. 



LETTER OF TRANSfllSSION. 

Letter of Transmission to Mayor pages 7 to 21 

Findings " 15 to 19 

Conclusions " 19 to 21 

REPORT. 

Report of Chief Engineer and Chemist pages 23 to 74 

Reasons calling for this report page 27 

Criticisms of Mr. McKenna's Letter pages 27 to 30 

Criticisms of Letter of Engineer of Department of High- 



ways, Borough of Brooklyn 

Scheme of Prof. Carmichael 

Scheme of Mr. R. L. Humphrey 

Correspondence with a manufacturer .... 

Purpose of our Research . 

Additional Notes on Cement Testing. . . . 

An Object Lesson 

Our method of Analysis and Conclusions. 



30 to 40 

45 to 47 

47 to 48 

49 to 53 

54 to 55 

55 to 69 

70 to 71 

71 to 74 



EXHIBITS. 



" A." Letter of Charles A. McKenna, which appeared in 

an Engineering Journal pages 77 to 81 

" B." Editorial which appeared in same Journal page 82 

" C." Quotations from Letter of Engineer of Department 

of Highways, Borough of Brooklyn pages 83 to 90 

" D." Report of S. F. Peckham to Chief Engineer, re- 
ferred to in answering report of N. P. Lewis. . " 91 to 93 

" E." Report of S. F. Peckham to Chief Engineer, re- 
ferred to in answering report of N. P. Lewis . . " 94 to 96 

Report of May 24, 1900 " 97 to 123 



TABLES. 

1. Physical Tests of 34 samples of Cement page 127 

2. Summary of Physical Tests " 129 

3. Chemical Analyses " 131 



LETTER OF TRANSMISSION 



OF 



Commissioners of Accounts 



TO 



Hon. ROBERT A. VAN WYCK, 

Mayor. 



LETTER OF TRANSMISSION. 



Office of the Commissioners of Accounts, ) 

Stewart Building, No. 280 Broadway, V 

New York, May 20, 1 901. ) 

SUBJECT: Notes on Cement Testing in addition to those 
submitted May 24, 1 900, 

also 

Answering Report 

of the Commissioners of Accounts 

to one made March 5, 1 901 , 

by the Engineer of the Department of 

Highways, Borough of Brooklyn, in reply to 

one made by the Commissioners of Accounts 

on violation of Specifications as to Concrete 

Street Foundations. 



Hon. Robert A. Van VVyck, 

Mayor : 

Dear Sir — As Commissioners of Accounts of the City 
of New York we beg to submit herewith for your considera- 
tion a report dated May 14, 1901, made to us by Mr. Otto 
H. Klein, our Chief Engineer, and Professor S. F. Peckham, 
Chemist in charge of our Laboratory. 

In order to clearly demonstrate the necessity for this 
report and its importance to the city, it becomes necessary 
to call your Honor's attention to the following facts, viz. : 



8 

That on May 24, 19CO, we submitted to you our printed 
report : 

'' Of a Comparison between Physical Tests and 
" Chemical Analyses of 34 Samples of Portland and 
*' Rosendale Cements." 

In said report we made use of the following language, 
viz. : 

*' On October 16, 1899, we made an additional report 
*' on violations of specifications for regulating, grading 
** and paving contracts, recommending the substitution 
" of Portland for Rosendale cement in concrete founda- 
" tions, and in said report called attention to the fact 
•' that our conclusion was also shared by the Engineers 
" of the Comptroller's office. ^ ^ *• 

" Copies of said reports of May 4 and October 16, 
" 1899, were, by your Honor, transmitted to the De- 
" partment of Highways, and shortly thereafter we were 
" visited by several of the cement manufacturers, and 
" the result of these interviews prompted us to send for 
" the above-named 34 samples AND MAKE A CARE- 
" FUL STUDY OF THE SUBJECT OF CEMENTS. 

" Attached to this report will be found Tables Nos. i 
" and 2, showing the results we obtained from physical 
" tests, and also Table No. 3, showing the results of the 
" chemical analyses of the 34 samples of cements. 

" (See pages 127, 129 and 131.) 

" In these tabulated statements the samples are 
*' designated by a separate series of numbers for each 
*' test, for the purpose of not disclosing their identity. 

" We realize the fact that up to the present time, so 
*' far as we have been able to discover, no correspond- 



" ence has been observed between physical tests and 
" chemical analyses of cements. 

" This lack of correspondence appeared to us after 
" the 34 samples had been analyzed, and, as a con- 
" sequence, we made the method of analysis the sub- 
" ject of investigation and developed a new process of 
" analysis which, upon being applied to these thirty-four 
" samples, the physical tests and chemical analyses 
" showed corresponding results as to the quality of each 
" sample of cement. 

*^ The report, which we herewith submit, will, we 
*' believe, show beyond a doubt and demonstrate our 
" finding that the chemical analyses of cements will 
*• always confirm \\v^ physical tests'' 



RESULT OF OUR PRINTED REPORT OF 
MAY 24, 1900. 

The report of May 24, 1900, from which we have just 
quoted, has been the subject of much correspondence and 
criticism, both favorable and unfavorable, from Manufactur- 
ers, Scientific Men and Writers on this subject, and the 
demand for copies for this country and Europe has entirely 
exhausted our first edition. 

Perhaps the most unfavorable criticism and which the 
Editor refused us the privilege of answering, appeared in an 
Engineering Journal of this City on August 18, 1900, in a 
letter signed by Dr. Charles F. McKenna, a commercial 
Chemist of this City, which letter, together with an editorial 
which appeared in said paper, will be found in Exhibits 
" A " and " B," pages 'jG to 82. 



Violation of Contract Specifications in Brooklyn. 

On November lo, 1900, about six months after the issu- 
ance of our Cement Report, we made an unfavorable report to 
your Honor on the violation of the specifications for laying 
a concrete foundation for an Asphalt Pavement on Watkins 
Street, Borough of Brooklyn, in which we reported that the 
physical tests made by us of the Rosendale cement used on 
this contract did not meet the very low requirements of the 
specifications of the Highway Department which form part 
of the contract between the Contractor and the City. 



Highway Engineer's Answering Report, Jan. 4, 1901. 

This report resulted in numerous answering reports be- 
tween our Bureau and that of the Commissioner of High- 
ways, the nature of which your Honor is informed, and 
finally we received, through your Honor from the Com- 
missioner of Highways, a letter inclosing a report dated 
January 4, 1901, of 11 pages, made to him by his 
Engineer of Brooklyn, under whose charge the Watkins 
Street foundation was laid. So much of said letter as is 
necessary for the purpose of this report will be found in Ex- 
hibit '' C," on pages 83 to 90. 



Commissioners of Accounts' Answering Report. 

In answer to the report of Mr. Lewis, Engineer of High- 
ways, Borough of Brooklyn, on March 5, 1901, we sub- 
mitted a report, of which the following is a copy, viz. : 



II 



New York, March 5, 1901. 



Subject: Answer in reference to 
Concrete Foundation 

on Watkins Street, ^Borough of Brooklyn- 
East New York Avenue 
to New Lots Road. 



" Hon. Robert A. Van Wyck, Mayor : 

*' Dear Sir — On December 13, 1900, we made a report to 
" your Honor regarding the inferior cement used in the con- 
" Crete foundation for the asphalt pavement on Watkins 
" Street, from East New York avenue to New Lots road, 
" Borough of Brooklyn. 

'*0n January 15 of this year, we received from your 
" Honor a letter transmitting a communication dated Janu- 
" ary 11, 1901, from the Hon. James P. Keating, Commis- 
'* sioner of Highways, with which was inclosed a report made 
" to the Hon. Thomas R. Farrell, Deputy Commissioner of 
" Highways, signed by N. P. Lewis, Engineer of Highways 
" for the Borough of Brooklyn. 

" Certain special examinations, the nature of which your 
" Honor is aware, occupied our attention so closely that we 
" could not, at the receipt of your letter, give the matter the 
'^ attention we at that time thought it deserved. 

" Said answering report of Engineer Lewis, of the Pligh- 
" way Department for the Borough of Brooklyn, consisted of 
" about eleven pages, and referred principally to Chemical 
" problems involved in the study of the composition of Ce- 
" ments, as seen by Mr. Broadhurst, the young Chemist of 
^' the Department of Highways. 



12 

" This answering report was based largely upon the let- 
" ter of Dr. Charles F. McKenna, published in the issue 
" of the Engineering Record of August i8, 1900, said 
" letter purporting to be a criticism of our methods of 
'' analysis of cement, as set forth in our report to your 
" Honor, dated May 24, 1900. 

" Inasmuch as we believe the criticism of Dr. McKenna 
" to be neither just nor sincere, it is needless to say that we 
** place no value on the statements contained in the report 
'* made by Engineer Lewis and his Chemist. 

" With the transmittal to your Honor of our printed re- 
*' port on Cements, dated May 24, 1900, our investigation of 
*^ the problems relating to the use and analysis of Cements, 
" was not closed, but has been in progress ever since, and is 
" still incomplete at this date. 

" We deem it prudent, for the time being, not to discuss 
*' the matters involved in the report of Mr. Lewis, believing 
*' that the time is not far distant when we may be able to 
" demonstrate, in a more practical manner than by a mere 
*' report to your Honor, the theoretical and practical cor- 
" rectness of our contentions. 

" For the present, we beg to quote the following letter 
" addressed to us by our Chemist in relation to the report 
" of Engineer Lewis and his young Chemist: 



" New York, January 26, 1901. 

" To the Commissioners of Accounts of The City 
" of New York : 



*• Gentlemen — I beg herewith to acknowledge 
' the receipt of the report dated January 4, 1901, made 
' to Hon. Thomas R. Farrell, Deputy Commissioner 
' of Highways, Borough of Brooklyn, New York 
' City, by Mr. N. P. Lewis, Engineer of Highways. 



13 

" This report has been given very careful consider- 
*' ation, especially as to the various statements and 
'^ conclusions contained therein that pertain to the 
" chemical analysis, and the chemistry of cements in 
*' general. 

*' To set forth in detail all the fallacies involved in 
" these statements and conclusions would require more 
" time and space than are now at my disposal. I 
*' would, however, briefly call attention to the follow- 
" ing paragraph : 

*• ' We, however, believe that the above 
" 'method of analysis to be a new, radical 
*' ' and arbitrary one and at variance with 
" * the usual practice, which is to employ 
" * concentrated hydrochloric acid, and de- 
" * termining all of the silica, alumina and 
*' ' iron oxides, and lime so decomposed 
. " ' from the silicates, aluminates, etc. 
" ^ This method has given entire satis- 
'* * faction in the past, and w^e see no 
** * reason for discarding it.' 

^' If improvements in analytical processes are con- 
" demned because they are * new, radical and arbi- 
" trary,' progress in analytical chemistry would be im- 
" possible. 

" The history of analytical chemistry for the last 
" hundred years consists of a perpetual succession of 
" processes and methods which might be characterized 
" as new, radical and arbitrary, in time becoming old 
'^ and time-honored, but finally ceasing to^'give satisfac- 
" tion, because new, radical and arbitrary processes and 
" methods ^n^xq proved to be better. 

" That the use of concentrated hydrochloric acid in 
" the analysis of cements has not ' given entire satisfac- 



14 

" ' tion in the past,' is proved by correspondence on file, 
" and also by the current literature of the engineering 
" profession for the last year, a literature with which 
" both Mr. Lewis and his Chemist, Mr. Broadhurst, 
" appear to be most surprisingly ignorant. 

" Respectfully submitted, 

'' (Signed) *'S. F. Peckham. 



" In conclusion, we wish to state, notwithstanding 
" Engineer Lewis's contention that he found some Cement 
*' which was used on this contract in question, which met 
" the requirements of the specifications, we found Cement, 
*' which did ;2<?/ meet the requirements of the Department, 
" and as the City pays a liberal price for concrete street 
"foundations, we contend that the supervision and 
" inspection by the Department of Highways, should be 
" of such a character as not to admit any material which 
" will not meet the very moderate requirements exacted 
*' by the specifications. 

" That these requirements are moderate, is conclusively 
" shown by the fact that several brands of cement, now on 
" the market, exhibit an excess of tensile strength of nearly 
" loo per cent. 

*' That defective Cement, in a considerable quantity, was 
" used in the concrete foundation on Watkins Street, is 
" demonstrated by the condition of the concrete itself, when 
" taken from the street in the presence of one of the 
" engineers of the Comptroller's office, weeks after it was 
" put down, and also by additional quantities, taken since by 
" our Engineer, and which are now in our possession. 

'* Respectfully, 

" (Signed) " John C. Hertle, 
Edward Owen, 
" CoDiniissioncrs of Accounts. 



15 



Findings. 



From the accompanying report of Messrs. Klein and 
Peckham, now submitted for your consideration, the follow- 
ing findings are submitted : 



First — That Mr. Lewis, the Engineer of the Highway Depart- 
ment of the Borough of Brooklyn, while contend- 
ing that wide differences are found between his 
results and our own, has by the results which he 
has stated, shown that those results are not only 
similar to our own, but that they confirm our 
own, when tabulated side by side. 

(See pages 31 to 38.) 



Second — That by the results exhibited by Mr. Lewis by 
the use of our method of analysis by his own 
Chemist upon similar specimens with our own, 
that similar results with our own are obtained ; 
and further, that his contention that our methods 
are unique and arbitrary, is not sustained by 
the chemists, eminent in cement analysis, who 
have reported to the Committee on Cement Tests 
of the American Society of Civil Engineers. 

(See pages 37, 38, 39, 45, 47 and 48.) 



Third — That the entire reasoning and conclusions of Mr. 
Lewis loses sight of, or ignores, those constituents 
of Rosendale Cement that are inherent in the ac- 
knowledged imperfections of its manufacture, viz. : 

The unburned and partially burned rock, 
which, while adding to the percentage of lime 
adds nothing to the percentage of cement. 

(See pages 33 to 36.) 



Fourth — That the results both physical and chemical, ob- 
tained by Mr. Lewis and ourselves, upon the 
Watkins Street Concrete, confirm each other, 
and when properly interpreted show that the 
COMMERCIAL ROSENDALE CEMENT 
used for that concrete is really quite a different 
material from that represented by the fallacious 
interpretation used by Mr. Lewis. 

(See pages 37 to 40.) 



Fifth — That the allegation of the Editor of the Engineering 
Record, which is nearly identical with that of 
Dr. McKenna, Mr. Lewis, and his Chemist, 
Mr. Broadhurst, that we apply the theoretical 
formula of pure Portland cements to natural 
(Rosendale) cements, is not sustained by any 
statement made in our report. 

(See pages 40 and 41.) 



17 



Sixth — That concerning the contentions of the gentlemen 
named in the fifth finding, regarding our method 
of analysis, we refer chemists to the schemes of 
Messrs. Carmichael and Humphrey. 

(See pages 45 to 48 and 71 to 74.) 



Seventh — That concerning the criticisms of a practical cement 
manufacturer, we refer to our answer. 

(See pages 49 to 53.) 



EightJi — That, at the same time our chemist was work- 
ing out his scheme of analysis which has 
provoked so much discussion, Professor Henry 
Carmichael, an acknowledged cement expert, 
formulated in entire independence, a scheme that 
is in most respects practically identical ; also that 
the scheme of Mr. Humphrey is radically dif- 
ferent from both Professors Carmichael and 
Peckham, and is not in accord with the generally 
recognized principles governing mineral analysis ; 
also that the criticisms of our correspondent are 
found by us, upon analysis of his own raw ma- 
terial and products, to be theoretical rather than 
practical, and are not justified. 

(See pages 61 to 69.) 



Ninth — That legitimate criticism of our method of analysis 
lies, not so much in respect to the method 
itself, as in respect to the condition of the 
sample submitted to analysis ; we on our part 
contending that inasmuch as the fineness of 
a cement is one of the qualities of a cement, and 
further, as our work has abundantly proved, that 
the solubility of cements depend upon their fine- 
ness, the samples of cement should be subjected 
to both Physical Tests and Chemical Analysis 
precisely as received at the Laboratory. We 
believe that our work has proved beyond any 
question that where the Physical Tests and 
Chemical Analyses are performed properly upon 
the samples as they are received, that the results 
correspond and confirm each other. 

(See Tables i, 2 and 3, pages 127 to 131.) 



Tenth — That, in proof of the inadequacy of Humphrey's 
method of analysis, we prepared a mixture of 
pulverized fire brick and Hme, which on analysis 
by his method, exhibited the silica, alumina and 
iron and lime, in the proper proportions for a 
first-class Portland Cement, while our own 
method exhibited it just as it was, viz., a mixture 
of insoluble material and lime, and not cement 
at all. 

(See pages 44, 70 and 71.) 



Eleventh — That our contention, that Rosendale cements are 
greatly inferior to Portland Cements for the 
making of concrete for street foundations is fully 
sustained, and that therefore Rosendale cements 
should not be used for that purpose. 



CONCLUSIONS. 



The Engineer of the Department of Highways for the 
Borough of Brooklyn, responsible for the concrete founda- 
tion on Watkins Street, Borough of Brooklyn, which was by 
us reported to your Honor, defends himself on the strength 
of the letter of Dr. McKenna and the editorial which ap- 
peared in the same journal on a previous date, and also upon 
the information which he received from the Chemist in 
charge of the Laboratory of the Highway Department. 

The necessity therefore devolved upon us of demonstrating 
the fallacy of the contentions, upon which the Engineer of 
the Department of Highways for the Borough of Brooklyn 
bases his conclusions, in order that the City may in the 
future, not suffer from the construction of improper concrete 
street foundations made of cement which is allowed to be 
used by public officials of The City of New York under 
erroneous conclusions based upon false premises. 



20 

We finally wish to present to your Honor and for the 
benefit of those officials who have not seen our first report, 
on a 

" Comparison between Physical Tests and Chemical 
'' Analyses of 34 samples of Portland and Rosendale 
'' Cements," 

the following statement : 

First — That complaints had reached this of^ce that, in 
some instances where asphalt pavements had failed, that the 
failure had been without doubt due primarily to the lack of 
the necessary strength in the concrete foundation. 

Second — That these complaints led to a general investi- 
gation of the cements used in these foundations and to the 
relation of Physical Tests to Chemical Composition. 

Third — That in the course of this investigation it was 
found that the Portland Cements of good quality of both 
Foreign and Domestic brands, tested from 50 to 100 per 
cent, above the requirements of the Department of High- 
ways for Portland Cements, and that they were more than 
200 per cent, above the requirements of the same Depart- 
ment for Rosendale Cements. 

Fourth — That the average Portland Cements, of a good 
quality, in the market exhibit a tensile strength of from 4.5 
to 6 times that required in the specifications of the Depart- 
ment of Highways for Rosendale Cements in Street Founda- 
tions. 

FiftJi — That while Portland Cements for use in street 
foundations are mixed with THREE PARTS of sand 
and from six to seven parts of broken stone, Rosendale 
Cements are mixed with TWO PARTS of sand and four 
parts of broken stone only, thus making the cost of a street 



21 

foundation laid of Portland cement nearly the same as that 
made of Rosendale cement. 

Sixth — That Mr. Lewis, the Engineer of the Department 
of Highways in the Borough of Brooklyn, in testing 79 
samples of " Commercial Rosendale Cement," used in 
street foundations in the Borough of Brooklyn, found that 
they averaged just above the ridiculously low requirements 
of the specifications of the Department of Highways, and 
that they ranged from below test to 40 per cent, above, 
and that more than 7 per cent, of the 79 samples were below 
test. 

Seventh — That notwithstanding this fact, and that Port- 
land Cements which are from 41^ to 6 times as strong as the 
requirements of the specifications of the Department of 
Highways for Street Foundations, and from the further fact 
that there is very Httle difference in the cost by the use of 
Portland Cement, Mr. Lewis, the Engineer of the Department 
of Highways for the Borough of Brooklyn, appears to be 
satisfied that " Comm.ercial Rosendale Cement " is a proper 
material from which to construct Concrete Foundations for 
asphalt Street Pavements. 

Eighth — That we do not agree with him, in this respect, 
nor do we believe that Rosendale Cement is a suitable 
material from which to construct any Street foundation, 
whether the surface be of asphalt, brick or any other 
material, when concrete four times as strong can be had 
for the same or nearly the same outlay. (See pages 32 
to 40). 

Respectfully submitted, 

John C. Hertle, 
Edward Owen, 
The Commissioners of Accounts. 



REPORT 



OF 



Otto H. Klkin 



AND 



Stephen K. Peckham: 



TO THE 



COMMISSIONERS OF ACCOUNTS, 



25 



REPORT OF 

Otto H. Klein and Stephen F. Peckham. 



ENGINEERING BUREAU. 
OFFICE OF THE COMMISSIONERS OF ACCOUNTS 

New York, May 14, 1901. 

Subject: Notes on Cement Testing, in addition to those 
submitted on May 21 and 24, 1 900. 



Hon. John C. Hertle and Edward Owen, Commissioners 

of Accounts : 

Gentlemen — We had the pleasure of bringing before you 
in a Report, dated May 21, 1900, the results of a research 
made by us that had been in progress for more than a year, 
in the Physical and Chemical Laboratories of The Commis- 
sioners of Accounts of the City of New York, upon the 
Relations between Physical Tests and Chemical Analyses of 
Cement. 



26 



CRITICISM OF FORMER REPORT. 

As might be expected, this Report has been made the 
subject of various criticisms, which are found to fall into 
three classes, viz.: 

First — Those which are wholly commendatory. 

Second — Those which are adverse, but given in courtesy. 

Third — Those which are of such a character as to be 
deserving only of silent contempt, except for certain consid- 
erations other than their merits. 



First Class of Criticism. 

As an illustration of the first class, we offer the following 
from one of the leading chemists of the country : 

" I am most deeply grateful for your thoughtful 
*' kindness in sending me copies of your very important 
" reports. I had occasionally been called upon to an- 
" alyze cements, according to the book method, but 
" always wondered what it availed my client. I have 
" often studied comparatively the tests of engineers 
" along with those of chemists, but always gave it up as 
" an insoluble puzzle. It is truly refreshing to have the 
" riddle solved as you seem to have done it." 

The second class will be discussed farther on. 



27 



Third Class of Criticism. 

To the third class belongs a letter addressed to the editor 
of The Engineering Record^ and which appeared in the 
issue of that Journal of August i8, i$oo, over the signature 
of Charles F. McKenna, a commercial chemist. 

In order not to make the body of the report too volumi- 
nous, we have attached a copy of said letter to this report 
and marked Exhibit "A," which will be found on page TJ. 



Reasons Calling for this Report. 

We desire to briefly reply to this letter on the following 
grounds, viz. : 

First — For the reason that we were refused that privi- 
lege by the Editor of the paper at the time the letter and 
editorial article appeared. 

Second — For the reason that this letter has been quoted 
and used by an official of the City of New York, in corre- 
spondence with our ofhce, and in criticism of the work'of this 
office, using it as an argument upon which to base what 
we believe to be wholly erroneous conclusions. 

Our Criticisms of Mr. McKenna's Letter. 

Paragraphs a and b of this letter are devoted to certain 
ethical considerations and to the expression of certain per- 
sonal opinions, unprofessional, and therefore wholly out of 
place in a discussion, where the argument stands or falls on 
the merits of a process of chemical analysis. 



Paragraph c is disingenuous and untrue. 

Paragraph d contains a number of assertions which are 
left without proof either by reference or discussion. That a 
method of analysis and the conclusions derived from it or 
by means of it, is absurd, because it is unique, may be the 
opinion of the author of the letter, but such an opinion 
finds little support from the history of chemistry. 

In paragraph e^ his discussion of the term " soluble 
silica," wherein he begs the question is simply hypercriti- 
cism ; it will be replied to farther on. 

In paragraph / he asserts, " he uses five grammes 
throughout the analysis without subdividing." -Je -h- -k- 
This statement is an absolute untruth, as any one can see 
by reading our paper. 

In paragraph^ the author of this letter shows himself so 
fresh in the matter of mineral analysis and such a blind 
adherent of what he considers established methods, that he 
condemns any attempt to test their accuracy. 

Why should any understanding be reached in reference 
to a matter of which we possess no knowledge ? 

Either the solution of cement in hydrochloric acid of 
varying strength gives constant and corresponding results or 
it does not. 

Either the manner of solution has an effect upon the 
determination of the constituents of the cement or it has 
not. 



29 

Moreover, the percentages of lime were not totals, as he 
asserts, but they were, like the percentages of soluble silica, 
the amount passing into solution in the acid of varying 
strength. 

The only astonishing thing about it is that Dr. McKenna 
should be willing to use a method of analysis, that furnished 
erroneous results and condemn a man for attempting to 
ascertain the facts and formulate a method capable of giving 
results more accurate. 

In paragraph h he does not make his meaning clear; but 
he appears to think that insufficient burning of a mixture of 
which limestone or marl is one of the constituents, will not 
result in the presence of carbonate of lime in the burned 
material, but that carbonate of lime when present in a 
cement must be purposely added as an adulterant. 

In paragraph i he says : 

" the carbon he finds he ascribes in all cases to unburnt 
" coal." 

The word coal cannot be found in our report, nor can one 
word be found there which refers to the source of the car- 
bon. The carbon is present all the same, in some cements, 
whatever its source may be. 

In paragraph k he assumes that we were not doing ex- 
actly what we had been doing for some months. This work 
with standard acid is not identical in results with the gravi- 
metric method described by us and was not mentioned by 
us. In course of time we expect to get to it. 



30 

We quite agree with Dr. McKenna in his conclusions 
stated in paragraph /. No one, so far as we know, be- 
sides Dr. McKenna has wasted any gray matter over " active 
index." 

In paragraph m, after asserting that we make an at- 
tempt which any one who reads our Report will find is 
exactly what we do not attempt, he finds it all " shockingly 
absurd." We quite agree that this paragraph is " shockingly 
absurd," if so mild a term will properly characterize it. 

We would like to believe that in writing this letter Dr. 
McKenna was sincere, but we find it impossible to accept 
the apology with which it closes. To do so would force us 
to question his intelligence. Moreover, we believe if he had 
been sincere his letter would have been carefully truthful 
and would have exhibited the manners of a professional gen- 
tleman, which it does not. 



Mr. N. P. Lewis' Letter. 

The official correspondence referred to in our " Second 
Reason," on page 27 of this report, is a letter dated Janu- 
ary 4, 1901, addressed by Mr. N. P. Lewis, Engineer of the 
Department of Highways for the Borough of Brooklyn, to 
his Deputy Commissioner, which finally reached us, for our 
attention, through his Honor the Mayor, on January 15, 
1901. 

A very careful examination of this letter at the time it 
was submitted led us to defer any extended reply to it until 
certain investigations then in progress had been completed. 



31 

As this letter involves a discussion of points of vital 
Interest in the cement problem, we quote from it at 
length, in order that the subject matter may be more 
clearly brought before you. 

So much of Engineer Lewis' letter as is necessary for the 
purpose of this report is hereto attached and marked Exhibit 
*' C," see pages S^ to 90. 



Our Criticism of Letter of Eng. Lewis. 

A general criticism of this letter of Mr. Lewis and of the 
letter of Dr. McKenna, which is quoted, lies in the atmos- 
phere of oracular profundity and occultism that pervades 
them. Thoughts too big for utterance seem to lie behind 
the obscure hints that are thrown_| out, but which are not 
fully stated. What is really meant by the authors can only 
be conjectured. Careful comparisons of what is plainly ex- 
pressed reveals the fact that Mr. Lewis' letter, including that 
of his chemist, Mr. Broadhurst, is as "shockingly" insincere 
as the letter of Dr. McKenna. 



Physical Tests of Commercial Rosendale Cement. 

Since Mr. Lewis has seen fit to make public, in this letter 
to the Department of Highways, the fact that the cement 
under discussion is Commercial Rosendale cement, we pro- 
ceed to use such evidence as is on record in this office and 
such additional evidence as Mr. Lewis has furnished in his 



32 

letter without regard to any private interests that may be 
involved. 

Four samples of this brand, numbered 45, 78, 83a and 
142, of cement have been subjected to physical tests in our 
Physical Laboratory, with the following results, viz. : 



One day's neat. . .. 
Seven days' neat . . 
Seven days' mortar 





45 


48 


pounds. 


87 


" 


172 


" 



78 



22 pounds. 
65 " 



83a 



30 pounds. 
67 " 
27 



142 



34 pounds. 
S3 " 
24 " 



Mr. Lewis makes use of the following language, viz. : 

*' As to lack of uniformity in these 79 lots, I will call 
" your attention to the fact that on one day neat tests 
" one lot showed over 70 pounds, two lots showed be- 
'' tween 60 and 70 pounds, 70 lots showed between 50 
" and 60 pounds, and 6 lots showed less than 50 pounds, 
" the lowest being 46 pounds and the average being 53 
'' pounds. 

" On the seven-day neat tests one lot showed over 
" 140 pounds, two lots showed between 130 and 140 
" pounds, 10 lots showed between 120 and 130 pounds, 
" 16 lots showed between no and 120 pounds, 
"one lot showed under no pounds, it being 106 
*' pounds, while the average was 120 pounds. * * * 
" The average results obtained when mixed with two 
" parts of standard sand were 7 days, 55 pounds." 

He does not give the details of the seven-day mortar 
tests. 



33 



Chemical Analyses of Commercial Rosendale 
Cement. 

There are in this office records of more or less complete 
analyses of four samples of Commercial Rosendale Cement, 
and Mr. Lewis' report furnishes us with two more. They 
are as follows : 





Commissioners of Accounts' 
Samples. 


Lewis' 
i Samples. 


Numbers. 


90a. 


90b. 


90c. 


279. 


Oct. 23. 


Nov. 2 5. 


In'^oluble in. lo per cent HCi . ... 


9-73 
0.72 
Trace. 
1-73 
8.65 


8.82 
Trace. 


23.98 
0.54 



1Q-15 


16.738 
0.182 
2.300 

Trace. 

13-17 


9.486 
, 0.985 
2.843 
0.760 
13.369 

27.44 


13.277 


Carbon . ... 




2.861 

0.759 
14.972 




Matter volatile at red heat 






20.83 




43-67 


32.39 


32.89 




15-24 

6.48 

53-76 


17.95 

8.42 

56.14 


7.92 

3-03 
42.86 


15.06 

6.97 

45-54 


14.74 

5-73 
52-10 


13-13 

5-44 

48.52 




Calcium oxide (lime) 






75-48 


82.52 


53-81 


f7.S7 


72.57 


67.03 



Discussion of these Results of Analysis. 



These results show, that Commercial Rosendale Cement 
is extremely variable in its composition, and that the vari- 
ation in the amount insoluble in 10 per cent. HCI is nearly 
100 per cent. 

This material consists of the constituents of the cement 
rock, that for the most part has not been sufficiently burned 
3 



34 

to cause the lime and silica and alumina to combine into 
soluble forms, and also of iron that has been burned suffi- 
ciently to render it insoluble in dilute acid, all of which is not 
cement, and performs no other office in the mixture than 
so much sand. 

The carbon adds, by whatever the amount may be, to 
this matter that is not cement. 

The magnesia and sulphuric oxide in these samples are 
not in excessive amount ; in, fact they are low in all of them. 

The next item of importance is the matcer volatile at a 
red heat, which varies by more than lOo per cent. It indi- 
cates directly the amount of carbonic acid remaining in the 
cement from insufficient burning, and indirectly either the 
impossibihty of making a uniform quality of cement from 
natural rock or else the lack of skill, or care, or both, in the 
manufacture of this particular brand of cement. The work 
that we have done shows that in these six specimens under 
consideration from 8 to i6 per cent, of them is carbonic 
acid, averaging at least 12 per cent, and representing in 
round numbers 27.25 per cent, of unburned carbonate of 
hme, or nearly, if not quite one-third of the limestone or 
cement rock. 

That these conclusions are sound is demonstrated by the 
physical tests. 

No. 90a on a seven-day mortar test gave 175 pounds, 
equal to 388 per cent of the tensile strength required. 

No. 90c gave 27 pounds, exactly 60 per cent, of the ten- 
sile strength required. Mr. Lewis does not mention the 
tensile strength of the cement of November 25, but it was 
doubtless up to the requirements. 



35 

Nos. 90a and 90c were taken off of works in Manhattan 
and Brooklyn. 

The strong cement No. 90a shows but 8.65 per cent, vola- 
tile at a red heat, which indicates about 8 per cent, carbonic 
acid, equivalent to 18.2 of carbonate of lime, containing 10.2 
per cent, of lime. 53.76 percent, less 10.2 per cent. = 43.56 
per cent, of lime in combination with 6.48 of alumina and 
iron oxide and 15.24 per cent, of soluble silica to form 
cement, equal to 65.28 per cent, of the amount taken. 

When this cement is mixed with twice the amount of 
sand, the mixture represents 65 parts of cement to 235 parts 
of sand, or roughly 1:3.5. (See physical tests page 32, 

No. 45-) 

No. 90c. shows 19.15 per cent, volatile at a red heat, 
which indicates about 16 per cent, carbonic acid, equivalent 
to 36.32 per cent, of carbonate of lime, containing 20.32 per 
cent, of lime. 42.86 per cent, less 20.32 per cent. == 22.54 
per cent, of lime in combination with 3.03 per cent, of 
alumina and iron oxide and 7.92 per cent, of soluble silica 
to form cement, equal to 33.49 per cent, of the amount 
taken. Where one part of this cement is mixed with two 
parts of sandj the mixture represents 33.49 parts of cement 
to 266.5 of sand, or roughly 1:8. (See physical tests, page 
32, No. 83a.) 

Mr. Lewis' cement of November 25, shows 14.972 per 
cent, of matter volatile at a red heat, which indicates about 
12 per cent, of carbonic acid, equivalent to 27.27 per cent, 
of carbonate of lime, containing 25.27 per cent, of lime ; 
48.52 per cent, less 15.27 = 33.25 per cent, of lime in com- 
bination with 5.44 per cent, of alumina and iron oxide and 
13.13 per cent, of soluble silica to form cement equal to 
51.82 per cent, of the amount taken. Where one part of 
this cement is mixed with two parts of sand, the mixture 
represents 51.82 parts to 248.18 parts, or roughly 1:5. 



36 

A certain bag or barrel contains a certain finely ground 
substance called Rosendale cement. All of the cement 
there really is, in either, is represented by the silica, alumina 
and iron oxide and lime that are so combined that they will 
form an hydraulic mixture. There may be a small quantity 
of plaster of Paris that adds something to the cohesive strengh, 
but it is not hydraulic cement. This cement is soluble in very 
dilute acid — even a 2 per cent, solution of glacial acetic acid 
dissolves it, as also other very weak solutions of organic 
acids. 

All that there is in the bag or barrel, that is not cement 
as above described, is worth less for purposes of making 
mortar than a like amount of clean sand. This material 
may be pulverized, unburned cement rock, or the same 
partially burned, the ashes of the fuel used, the pulverized 
fine fragments of the fuel used (which we call carbon, but 
which Mr. Lewis calls " Insoluble matter volatile on igni- 
tion "), iron oxide which has not combined to form cement, 
magnesia, sand, etc. 

Where these materials are present in moderate amount, 
as in No. 90a, the mortar resulting from its use is nearly as 
strong as Portland cement mortar. Where they are very con- 
siderable in amount, as in the sample of November 25, the re- 
sulting mortar is not worth more than half as much as Port- 
land cement mortar. Such cement as is represented by 90c 
is good for nothing. 



The Watkins Street Cement. 

This bran(,l of cement was used on Watkins Street, 
Brooklyn, and has been analyzed by ourselves and by 
Messrs. Lewis and l^roadhurst. Our own analysis is No. 
279. There are no difTerences between the three samples, 
as shown by the analyses, that are of any practical value. 



37 

They all three belong to the class above mentioned, where 
the materials above mentioned, that are not cement, are found 
in very considerable amounts, resulting in a mortar, that at 
best, is not worth more than one-half as much as Portland 
cement mortar. 



The Watkixs Street Concrete. 

The concrete that has been produced from the use of this 
cement has also been investigated by ourselves and by 
Messrs. Lewis and Broadhurst. 





Separation of Samples of Conxrete according to 




COMMISSIONERS OF ACCOUNTS. 


LEWIS. 


XUMBE-RS. 


280A. 


280B. 


H59. 


H60. 


Total weight of samples . . . 

Weight of stone 

Per cent, of stone 

Weight of mortar. 


595 grams. 

60 per cent. 
235 grams. 
40 per cent. 


832 gram=. 
547 " i 

65 per cent. 
285 grams. 

35 per cent. ' 


1,059.09 grams. 
668.50 " 

63.12 percent. 
390,59 gr^ms. 

36.88 per cent 


3,794.05 grams. 
2.563-95 " 

67.59 percent. 
1,230.1c gram?. 

32.41 per cent. 





These results show an extreme difference in the mixture 
of stone and mortar in the four samples of 7.5 per cent. 
There is about the same difference between Lewis' samples 
as between our own. As Mr. Lewis' results were computed 
on larger samples they may be more nearly correct, but the 
differences do not appear to us to be material. 



The mortar was air dried and sifted from the stone. Our 
samples effervesced freely when introduced into 10 per cent, 
dilute hydrochloric acid, and we have no doubt the others 
did, but Mr. Broadhurst does not mention it. 



38 



The matter insoluble in the acid consisted of : 



Numbers, 

Insoluble Matter. 

Sand and other mineral matter 

Carbon 

Total 

Soluble Matter. 

Silica 

Alumina and Iron Oxides 

Lime 

Magnesia 

Sulphuric Oxide 



Commissioners of 
Accounts. 



28gA 



69.60 
•52 



70.12 

3.68 

5.35 

12.44 

Trace 



92.09 



280B 



7'-35 
•63 



338 

3-56 

12.59 

Trace 



Lewis. 


H59 


H60 


71.18 


71-34 


.70 


.83 


71.88 


72.17 


1 
! 

1 3-62 


3.46 


1 2.85 


2.8r 


13-78 


13.46 


Trace 

i 


Trace 


92.13 


91.90 



These results, like those determining the proportions of 
the concrete, are as nearly alike as could be expected, and 
confirm each other. 



Discussion of the Results of Analysis of the 
Concrete. 



We do not, however, agree with the conclusions that 
Messrs. Lewis and Broadhurst have drawn from them. The 
statement is made in Mr. Lewis' letter, paragraph 12, that, 
" this Commercial Rosendale cement contains approximately 
30 per cent, of so-called " Inert matter" (Matter Insoluble in 
10 per cent. Dilute hydrochloric acid) we do not know of 



39 

any Rosendale cement which contains 15 per cent, of matter 
corresponding to this figure." 

It is fortunate that Mr. Lewis took so much pains to state 
exactly what he means and also that he means by matter 
insoluble in 10 percent, dilute hydrochloric acid exactly the 
matter referred to in Exhibit " E " of this report on pages 94 
to 96, when we based certain calculations on an assumption of 
a Rosendale cement containing 1 5 per cent, of matter insoluble 
in 10 per cent, dilute hydrochloric acid. Some of them con- 
tain a great deal more than 15 per cent, of such matter, but 
none that we have examined contained 30 per cent. 

Referring to our table, on page 33, we find that of these 
six samples of Commercial Rosendale cement, three of which 
are from our former report, and two from Mr. Lewis' letter, 
the matter insoluble in 10 per cent, dilute hydrochloric acid 
is 9.73, 8.82, 23.98, 16.74, 9.49 and 13.28, of which the 
average is 13.67. 

Mr. Lewis shows in Exhibit '' C,'' paragraph 11. that a 
mortar consisting of one part cement to two parts of sand by 
volume, contains by weight 71.33 per cent, of sand, and 28.67 
per cent, of cement. 13.67 per cent, of 28.67 = 3.86 pounds 
of inert matter in the amount of this average Rosendale 
cem_ent contained in 100 pounds of mortar. 3.86 added to 
71-33 — 75-19 which leaves 24.81 of cement, provided the 
cement is cement ; but we have already shown (on page 34) 
that this cement containing at least 12 per cent, of carbonic 
acid is at least one-quarter carbonate of lime, amounting 
to 6.2 per cent, or 6.2 pounds which should be added to the 
75.19 pounds = 81.39 pounds of inert matter to 18.61 
pounds of cement in 100 pounds of dry mortar. 



40 

Estimating Commercial Rosendale Cement, as ce- 
ment, it is easily shown that the mortar used on 
Watkins Street filled the requirements of the specifi- 
cations. Estimating this cement at what it really is, a 
mixture of cement, carbonate of lime and other inert 
matter, it is not surprising that one month after the 
concrete was laid the mortar could be pulverized be- 
tween the fingers and removed from the stone with 
the thumb nail. 

Instead of being 75.19 of inert matter lo 24.81 
parts cement, the mortar made from these Commer- 
cial Rosendale cements, consists of 81.39 parts to 
18.61 parts; in other words, there is only about three- 
fourths as much cement in the mortar as the specifi- 
cations call for. 



FURTHER CONSIDERATION OF CRITICISM OF 
FORMER REPORT. 

Returning to the criticisms of our report of May 24, 
1900, as shown below, we beg to consider them under "Four 
Specific Allegations," viz. : 



First Allegation. 

**' That we carried on our investigations of Rosen- 
" dale cements along the same lines as our investiga- 
" tions of Portland cements, and that such position is 
" untenable. 

In reply to tliis half truth, we quote from our former 
report, as follows : 



41 

" It could not be expected that a cement made by burn- 
" ing a natural lime rock containing clay and silica, would 
" be found, on chemical analysis, to conform in its composi- 
" tion to any theoretical formula. The fact that natural 
" cements do not, could not be more forcibly demonstrated 
" than by an inspection of the accompanying table. 
" * * " No other results could be expected from 
*' careless and rapid burning of stone in large lumps in kilns 
" or stacks than great lack of uniformity in the result and 
" consequent uncertainty as to the value of the product." 

While we believe this statement to be a sufficient reply 
to this puerile and insincere criticism, we remark further, that 
we have never observed any claim that there was one chemi- 
cal compound that formed the hydraulic portion of Portland 
cements and another and different compound that made 
Rosendale cements hydraulic. We think any such claim 
cannot be sustained, and, therefore, that any direct or in- 
direct attempt to advocate the use of Rosendale cements as 
equivalent to Portland cements on such grounds is both 
injudicious and unfair. 

The constant soliciting of consideration for Rosen- 
dale cements that is not extended to Portland ce- 
ments, is in itself a confession of weakness and is, in 
our judgment, in the long run bound to react un- 
favorably. 

We have never claimed that Rosendale cements " con- 
tain ingredients in such proportions as to make a theoreti- 
cally perfect cement." 



42 



Second Allegation. 

" That our methods of analysis are new and unique, 
'' radical and arbitrary, and at variance with the usual 
*' practice," etc. 

If improvements in analytical processes are condemned 
because they are new, etc., then progress in analytical 
chemistry would be impossible. The history of analytical 
chemistry for more than a century consists of a perpetual 
succession of processes and methods which might be char- 
acterized as new, radical and arbitrary, which in time be- 
came old and time-honored, but which finally ceased to give 
satisfaction, because other new, radical and arbitrary pro- 
cesses and methods were proved to be better. 



Third Allegation. 

** That the use of concentrated hydrochloric acid-has 
*' given entire satisfaction in the past." 

That this statement is wholly incorrect is proved by cor- 
respondence on file in our office and also by the current 
literature of the engineering profession for the past year, 
which we shall quote farther on in this report, a literature 
with which we are surprised to find both Mr. Lewis and his 
chemist, Mr. Broadhurst, apparently unfamiliar. 



43 

Fourth Allegation. 

Contained in paragraph 8 of Mr. Lewis' letter. 

" It would appear as though the chemist had first in- 
'* tended to examine the concrete as a whole, but he sub- 
" sequently confined his investigations to the mortar." 

This statement is not clear, as the stone was nothing but 
fragments of old bluestone curbing ; why should a chemist 
examine them ? 

The chemist did exactly what he intended to do, viz. : 

To determine the proportions of stone and mortar, and 
this he found to be practically the same as did Mr. Lewis. 

If Mr. Lewis had been sincere in his comparison, he 
would have given our percentages and shown them to be 
practically the same as his o'wn. He would also have used 
the words " inert matter " ; in one sense instead of two^. 

Mr. Lewis defines his use of the words "inert matter" to 
be the matter insoluble in lO per cent, hydrochloric acid 
and then proceeds to use the term to signify t?ie "inactive 
constituents " of the cement, which includes everything in 
the sample that is not cement. 

If the words are used as he defines them, it is perfectly 
correct to consider that an average sample of Rosendale 
cement will contain 15 per cent, of such inert matter. 



44 

If he uses the words as equivalent to inactive constituents 
then 30 per cent is the proper figure. 

It is very apparent from his definition of the term and 
use of it, that his reasoning in paragraph 12 is insincere and 
that he knew he was not constructing his argument upon 
premises laid down by the Commissioners of Accounts, in 
their Report of May 24, 1900, as he alleges in paragraph 13. 



45 



The Second Class of Criticisms. 

As concerning the second class of criticisms and before 
proceeding to discuss the merits of the method of analysis 
which was described in our former Report, we wish to call 
attention, first, to the 

"'Progress Report of the Special Committee on the 
" * proper manipulation of tests of cement,' made to 
" the American Society of Civil Engineers, and pub- 
** lished in the Proceedings of that Society, Vol. XXVI, 
" No. 4, April, 1900." 



This report consists of the various replies, to a long list 
of questions, offered by many persons, and submitted by the 
chairman of the committee. Prof. G. ¥. Swain, without 
comment. 

Scheme of Prof. Henry Carmichael. 

In reply to Question 5, 

Wkat elements of compotcnds should be determined ? 

Professor Henry Carmichael of Boston (who is an 
acknowledged authority as a cement expert), says : 

" HydrauHc cement consists of a double siHcate of Hme 
*' and alumina (including iron oxide), which is readily 
'^ soluble in dilute hydrochloric acid, leaving little or no 
" insoluble residue. In addition to the soluble silica 
*' and the oxide of calcium, aluminum and iron, good 
" cement contains traces of the oxides of magnesium, 
" sodium and potassium, together with traces of carbon- 
" ates, sulphates, chlorides and combined water, and 
" finally minute amounts of insoluble sand or cinder." 



46 . 

In reply to Question 6, 

" W/iat do you consider the best methods of determining 
these compounds with sufficient accuracy ? " 

Prof. Carmichael continues, 

' The sample is ground fine in an agate mortar. One 
^ gram is carefully weighed out in a shallow porcelain 
' dish and well covered with a 3 per cent, solution of 
' hydrochloric acid. After several hours the cement 
' should completely dissolve in this acid with the excep- 
' tion of a small amount of sand, mostly black cinder, 
' from the fuel employed in making the cement. The 
' residue, if any, is filtered off and determined. The 
' clear solution is evaporated to dryness on a water bath 
' in a flat dish. Hydrochloric acid is poured over the 
' dry residue, and the acid is then evaporated. Add a 
' few drops of same acid, again drive off acid. Moisten 
' residue again with same acid and boil up with pure 

■ water. The silica is rendered insoluble by the above 
^ operation and can be filtered off and weighed. The 
' silica which thus dissolves in the dilute acid, and is in 
' turn rendered insoluble, is the silica which is available 
'Jn the setting of the cement. The filtrate from silica 
' is boiled with a few drops of nitric acid, and pure 
' ammonia is then added, which precipitates the oxides 
^ of iron and aluminum. With the ammonia is added 
' also ammonium chloride in sufficient quantity to 
• retain the lime in solution. After boiling for some 

■ time, the oxides of iron and aluminum are filtered off, 
' and after drying are ignited and weighed." 

Here follow directions for separating the iron and 
aluminum : 

" To the filtrate from iron and aluminum oxides is 
" added a slight excess of ammonium oxalate, whereby 
" the lime is precipitated as oxalate which is filtered 
" off, ignited at a dull red heat in a platinum crucible 
*' and weighed as carbonate." 



47 

His scheme offers further details for the determination of 
the ingredients that he says are found in good cements in 
traces ; for the determination of water and carbonic acid by 
ignition ; and for the determination of free lime by titration. 

This scheme closely resembles our own, while differing 
from it in several important respects. It was worked out 
without any knowledge whatever on the part of either party 
concerning the other. A proper comparison will show that 
many of the puerile criticisms indulged by Dr. McKenna 
concerning our paper, apply with equal force to the scheme 
of Prof. Carmichael. 



SCHEME "OF R. L. HUMPHREY. 

Following the scheme of Prof. Carmichael is another 
scheme by R. L. Humphrey, who writes as follows : 

'' One-half gram of the finely pulverized sample 
" dried at ioo° C, is thoroughly mixed with four or five 
" times its weight of sodium carbonate, and fused in a 
" platinum crucible until CO^ no longer escapes ; the 
" crucible and its contents is placed in a beaker, and 
^' twenty or thirty times its quantity of water, and about 
" lo c.c. of dilute HCl is added ; when complete solu- 
" tion is effected, it is transferred to a casserole and 
'^ placed on a water bath, and evaporated to dryness 
'* several times. The mass is taken up with dilute HCl 
" and water, heated for a short time and filtered, wash- 
" ing the residue on the filter thoroughly with hot water. 
" The filter is dried, ignited and weighed. This weight 
^' (less ash) gives the amount SiOg." 



48 

" The filtrate is brought to boiling and ammonium 
'' hydrate added in slight excess, the boiling is continued 
" until the odor of ammonia is no longer perceptible. 
'' Filter and wash. Redissolve in hot dilute HCi, again 
" precipitate with ammonia and filter through the pre- 
" vious filter and wash with boiling water. The precipi- 
** tate dried, ignited and weighed, less ash, gives the 
" amount of AI3O3 and FegOg." 



Then follows a method of separating iron from alumina : 

" The filtrate from the iron and alumina is heated to 
"boiling, and boiling ammonium oxalate is added until 
" a precipitate is no longer formed. After boiling for a 
*' few minutes, it is set aside for a short time ; when 
" the precipitate has settled perfectly, decant the clear 
"liquid through a filter, wash by decantation, dissolve 
"the precipitate in hot dilute HCI, using as small a 
" quantity as possible to effect a complete solution, heat 
"to boiling and add ammonia, heat on a water bath for 
" a few minutes ; when the solution clears, filter through 
" the previous filter, wash thoroughly with hot water. 
" Dry the precipitate, ignite to constant weight, and 
'' weigh as CaO ", or determine the lime volumetrically 
"by titration with potassium permanganate." 

He then determines the ingredients occurring in small 
proportion. He determines S03 in a separate portion after 
removing the silica. 



49 
Correspondence. 

We wish to call attention secondty, to correspondence 
which we have lately held with a prominent manufacturer 
of cement, in which he indulged in the following criticisms of 
our paper. 

{a) " Experiments we have made show that the 
" solubility of commercial Portland cements in dilute 
'' acid depends greatly upon tne fineness of grinding." 

{b) " We have found no cements which if ground to 
'' extreme fineness in an agate mortar, show more than 
" a fraction of one per cent, of insoluble matter." 

(c) " It seems to me therefore, that your separation 
" of the components of cement into active and inactive 
" constituents is not well grounded." 

(d) '' I think it probable that the active index Avould 
" be somewhat reduced if the cement is dissolved as 
" completely as possible." 

(e) '' Since even the monosilicate of lime, wallasto- 
" nite, is readily decomposed by acid, it is evident that 
" the residue should contain practically no lime, and 
" would consist of a minute amount of uncombined clay. 

(/) " It is impossible that this should reach more 
*' than a fraction of one per cent, in a good cement. 

(g) " Would say further that the use of sufficiently 
" dilute acid and fine grinding will give a clear solution 
" without any separation of gelatinous silica. 

{/i) " In my opinion no conclusion can be drawn 
" from the amount of lime soluble in water. 

(2) *' This would also depend greatly on the degree 
" of pulverization. [n) It is generally held, as you 
" know, that all cements are decomposed by water into 
" calcium hydrate and a hydrated monosilicate. (lii) If 
" this is true, the action of water would be progressive, 
" and prolonged action of sufficient water would dis- 
*' solve out all the lime, (iiii) In fact, Le Chatelier 
*' found this to be the case." 
4 



50 



Our Answer to Manufacturer's Criticism. 

To which we replied : 

The first sentence of your letter furnished a key to the 
whole matter. You say : 

" That experiments we have made show that the 
*' solubility of commercial Portland cements in acid de- 
" pends greatly upon the fineness of grinding." 

Believing that this fact as stated by you has been proved 
beyond any question, we insist that every sample of cement 
shall be analyzed in exactly the condition in which it is 
brought to the laboratory ; that is, that the specimen shall 
be neither dried nor pulverized^ nor in any manner treated 
in such a way as to either lessen or increase the differences 
that exist between the samples as they are brought upon the 
works or are subjected to physical tests. 

We have not yet found a weighable amount of lime in 
any of the residues from dilute acid that we have examined. 

We think that if you read our paper carefully you will 
see that no conclusions are drawn from the amount of lime 
soluble in water. It is, however, an observed fact that all 
of the good cements contain about 5 per cent, of such 
soluble lime. 

If you would advocate the uniform grinding of samples 
of cement to an impalpable powder, in an agate mortar, in 
order that they may be more completely dissolved and 
brought into solution, we insist that we do not agree with 
you. 



51 

We believe that cement of proper fineness for use is 
soluble in lo per cent, hydrochloric acid without gelatiniza- 
tion, and that any matter not so soluble, contained in com- 
mercial cement, is not cement at all, and is, and should be 
classed as, ' inert matter.' " 

To which he replied, 

{J) "your separation of the constituents of cement 
"into 'active and inactive constituents' by the action 
" of 10 per cent, hydrochloric acid on the commercial 
" cements, appears to me to be without foundation. 

{k) " The varying amounts of insoluble matter 
*' obtained by you on treating the same cement with 
" acid of varying strengths and in various ways appear 
" to show that the amount of insoluble matter depends 
" upon the method employed, rather than upon the 
" chemical character of the cement analyzed. 

(/) "I have found that most commercial Portland 
" cements, if ground to great fineness, give scarcely any 
" insoluble residue on treatment with sufficient quantity 
" of 5 per cent. acid. 

{m) " The high percentage of insoluble matter 
" obtained by you simply results from the compara- 
" tively coarse grinding of the cement. 

{n) " You certainly will not contend that the com- 
^' position of the coarser particles is materially different 
" from that of the fine ones, or that the chemical char- 
" acter of the cement is changed by grinding the coarse 
" particles to uniform fineness with the rest. 

(<?) "Your choice of lo per cent, acid and method 
" of mixing appear to me to be wholly arbitrary, and the 
" conclusions drawn from the amount of insoluble mat- 
^' ter obtained to be quite unjustified. 

(/) " Since coarsely ground cement gives a consider- 
^' able residue when treated with dilute acid, while finely 



52 

" ground cement gives practically none, and since this 
" residue consists chiefly of silica, and contains, as 
** stated by you, practically no lime, it appears to me 
** evident that this insoluble matter results chiefly from 
*' local separation of silica contained in the coarse 
" particles. 

[q) " The lime and other constituents contained in 
" these particles are, however, dissolved, and are in- 
" eluded by you in the group of active constituents. 

(r) '^ The injustice of this is apparent. 

{s) " If the silica of the coarse particles is inactive, 
" the lime must be so also. 

(t) " It is undoubtedly correct to submit commercial 
" samples of cement to physical tests as they are re- 
'^ ceived, without grinding. 

{u) " To submit these samples to chemical analysis, 
*^ however, without bringing them into homogeneous 
'* condition by grinding, is certain to lead to erroneous 
" conclusions. 

{v) " In burning, however, a disturbing factor enters, 
" and this is the ash of the coal dust used as fuel. 

{w) " This ash adds at least two per cent, to the 
" silica, alumina and iron oxide of the product. 

{x) " It is, however, brought into combination with 
" the lime of the charge sufficiently to become wholly 
*^ soluble in acid, but not uniformly enough to allow 
" the lime of the raw material to be raised to a corre- 
" sponding extent. 

(j) " I believe fully that the best Portland cements 
" are thoroughly homogeneous in character, and that 
" the excess of silica, alumina and iron over that called 
" for by the formula is due to the ash of the fuel and to 
'* the general practice of carrying the lime a little below 
" the maximum in order to offset possible fluctuations 
" in the mixture." 



53 

We asked our correspondent to send us a sample of the 
fuel ash. 

He replied : 

(^) " It will be impossible to send you a sample of 
'^ th,e coal ash to which you refer, as this melts in with 
" the clinker with which it comes in contact in the 
" rotary kilns. 

{za) " The amount of fuel used is about 150 pounds 
'' to the barrel of cement. 

{zb) " The ash of this fuel is about 8 per cent., and 
*' if all absorbed by the clinker would add about 3 per 
*• cent of silica, iron and alumina to the latter." 



54 

THE PURPOSE OF OUR RESEARCH. 

We wish to discuss in association these methods of 
analysis and this correspondence, all of which comes from 
unquestioned authority and is strictly professional, all of 
which represent a purpose that is in fundamental opposition 
to our own purpose, together with the letters and reports 
previously cited. 

The purpose of the research described in our former 
paper was to ascertain, whether or no any correspond- 
ence could be established between the results of a 
chemical analysis and the physical tests of cement. 
It was not to defend or defame any brand of cements, 
to contrast any one cement with another, or to contrast 
American cements with foreign cements, or one class 
of foreign cements with another class of the same, al- 
though some very unexpected results obtained from 
the research led incidentally to such comparisons. 

This object was kept clearly in view from first to last and 
while the different brands of cement examined represented 
in nearly every case nothing but a name ; still, the different 
samples were designated wholly by numbers that were pur- 
posely made different in the two laboratories. 

The cements first analyzed were brought to the office 
from various works in progress in the City, and they gave 
results that were extremely unsatisfactory apparently for vari- 
ous reasons that we do not care to take the time and place to 
discuss here. 

Keeping the object of our research in view, we sohc- 
ited samples of freshly ground cement from a number of 
manufacturers and dealers, and we still found that when 



55 

these fresh, and in most instances, high class cements were 
analyzed by the methods described in the books, that no cor- 
respondence could be observed between the physical tests 
and chemical analyses. 

Believing that Nature could not contradict herself, we 
were convinced that there must be some defect in the ques- 
tion put to nature, in the chemical analyses ; in other words, 
that the chemical analysis was not properly conducted. This 
led us to conclude that the purpose of an analysis was not 
satisfied when an, in some respects, inadequate method of 
ultimate analysis was followed. 



ADDITIONAL NOTES ON CEMENT TESTING. 

THE COMPOSITION OF CEMENTS. 

For, no cement, either Portland or Rosendale or slag, on 
the market, consists of chemically pure hydraulic cement. 
Assuming the correctness of the researches that led up to 
and include those of the Messrs. Newberry, we have a right 
to further assume that hydraulic cement consists of tri-calcic 
silicate and ferro-aluminate in the proportions indicated by 
the equation. 



CaO ^ 

2.8 X Silica) + (i.i x Alumina & ferric oxide) 



A commercial Portland cement therefore consists of 
the above-named compound plus, not a trace, but an 



56 

unavoidable percentage of the ashes of the coal employed as 
fuel, 

Also of overburned clinker, 

" under burned clinker, 

*' uncombined clay, 

" Magnesia, 

" Sulphuric oxide, 

" Alkalies, and 

" a small percentage of water and COg. 

In the^case of Rosendale cements, there is in addition to 
these an unavoidable percentage of both overburned and 
underburned cement rock, particularly the latter, together 
with more or less minute fragments of the fuel used that are 
ground up with the cement and appear as carbon. 

We assume that these impurities are unavoidable, because 
from the nature of the case no cement can be manufactured 
without them and no cement that we have examined has 
been entirely free from them, and we believe that we have 
examined some of the best cements now made in the world. 

The amount of carbon ranged in those we have examined 
from zero to nearly 2 per cent. This carbon is not a proper 
constituent particularly of a Portland cement. No good 
cement contained more than a trace of it. It is, and must 
be from the nature of the case, a source of weakness, 
especially when it is in the form of an oily soot from 
imperfect combustion of oil used as fuel. 

These methods of analysis do not offer any opportunity 
for the determination of this impurity, and it does not make 
it anything but carbon to call it " Insoluble matter volatile 



57 

Also of Plaster of Paris, introduced purposely to in- 
fluence the setting of the cement. When moderate in 
amount this is not an injurious ingredient. 

Also, a percentage of quartz sand. Stillman's and 
Humphrey's methods of analysis offer no opportunity for 
the determination of this ingredient. 

Also a percentage of underburned rock or clinker which 
results in the presence of carbonate of lime, which is inert, 
having no cementing properties. That it is possible to 
manufacture a Rosendale cement, containing but little of it 
is shown by analysis No. 90a, page 33. 

StiUman's and Humphrey's methods furnish no oppor- 
tunity for the determination of this ingredient. 

Cements made from marl are liable to contain Glauconite, 
which is a mineral containing a comparatively large amount 
of Alkalies. Cements made from slag are also liable to con- 
tain alkahes. We have no reason to suppose, however, that 
alkalies exist in any of the samples that we have examined 
in any injurious amount, and they were therefore not 
determined. 



The Question Put to Nature. 

The question therefore to be put to Nature is, how 
much Hydraulic Cement does this mixture contain as 
it is brought to the Laboratory? And what else does 
it contain that it should not? 



58 



How THE Question is Answered. 

In order to answer this question, it may first be deter- 
mined how much of the sample of the cement is volatile at 
a bright red heat. We have found by repeated examples 
that an ordinary Portland cement of good quality will give 
about 4 per cent, or less, of a matter volatile at a red heat ; 
with Rosendale cements the amount is much greater. 
A number of tests showed that this amount was not materially 
increased by the use of a blast lamp. In a few instances the 
increase amounted to a few tenths per cent, but in a majority 
of instances it was not appreciable. This loss at a red heat 
was found in a majority of instances to very nearly 
correspond with the amount of carbonic acid determined 
directly, but in those instances where this loss was large, 
amounting to more than lO per cent, the difference between 
these two factors increased as the loss increased, showing 
that in those cases where this loss is large, an increasing pro- 
portion of such loss is water. If more satisfactory, the per- 
centage of carbonic acid can be directly determined, but 
even when it is so determined, the matter volatile at a red 
heat should always be ascertained. 



The Sample should be Analyzed as Received. 

The problem of analysis is simply an ordinary problem 
in mineral analysis. The physical tests have been made 
upon the sample as brought to the Laboratory and in such a 
manner as to exhibit the greatest possible differences be- 
tween this sample and all other samples. The samples were 
neither dried nor pulverized, because either drying or pul- 



59 

verizing, or both, would make another and different sample 
to be tested from the one submitted. Our correspondent 
admits this, and if he did not everybody else does ; yet, re- 
ferring to his sentence marked (zi) he claims that to submit 
these samples to chemical analysis, without bringing them 
into homogenous condition by grinding, is certain to lead to 
erroneous conclusions. Both schemes of analysis that we 
have quoted require that the sample shall be ground, and 
one of them that it shall be dried. We have found the loss 
that good cements sustain when dried at ioo° C, is not of 
practical importance, with bad cements it is otherwise. 

We believe that right here, is the keynote to the 
controversy, and that in discussing any subject the 
disputants must be agreed as to their subject or they 
may argue forever and both be correct in reaching 
diametrically opposite conclusions. 

In this case the two chemists and our correspondent are 
agreed that the samples should be pulverized to an impal- 
pable powder, and we, on the contrary, believe that as soon 
as a sample is pulverized it is converted into a new sample. 
This our correspondent practically admits. (See sentences 

We claim that the sample should be analyzed as received 
and thus made to exhibit the greatest possible differences, as 
is the case in the physical tests. If the samples are pulver- 
ized and thus brought uniformly into solution, certain differ- 
ences are lost, and it is not strange that the physical tests 
and chemical analyses do not correspond. 

The same result follows when the samples are fused with 
sodium carbonate and when the sample is dissolved in con- 



6o 

centrated HCl. In both instances the distinction between 
the silica that is combined into, tri-calcic-ferro-alumino-sili- 
cate or cement, and the siHca that exists as sand or fuel ash 
in unburned clay is lost. 



Active and Inactive Constituents. 

In our former report we did not base any distinction of 
"active" and "inactive" constituents on the action of lO 
per cent. HCl (<?, j). We base those distinctions on the 
researches of the Messrs. Newberry and we insist that if 
those researches are conclusive, as we believe that they are, 
our conclusions follow from the nature of the case. There 
was nothing arbitrary in using lO per cent. HCl. It is 
nothing but the ordinary dilute HCl found on every labora- 
tory shelf There is nothing arbitrary in using a sieve to 
scatter the cement upon the acid and prevent the develop- 
ment of sufficient heat to render a part of the silica insoluble. 

Moreover, our correspondent admits that a theoretically 
perfect cement will contain, in spite of anything, 3 per cent, 
of fuel ash and i per cent, or less of unburned clay, {y, w^ 
X, z, zz, zzz.) As these materials are not cement, why should 
they or any part of them be brought into solution with the 
cement, if it could be avoided ? 

Let us suppose that an unskillful or dishonest manu- 
facturer uses more coal than is necessary or poor coal, and 
thus increases his coal ash to 6 per cent, and his unburned 
clay to 4 per cent., why should the 6 per cent, be dissolved 
by fine grinding or the 10 per cent, be dissolved by fusing 
with sodium carbonate ? 



6i 



In other words, why should a method of analysis be 
pursued that destroys all differences, while the physical 
tests are conducted in such a manner as to exhibit all 
differences? 



Proof that this Contention is Correct. 



That this contention is correct is proved by the results of 
our analytical work. 

Chemical Laboratory sample No. 149. Physical Labor- 
atory sample No. 88, was a cement that gave the highest 
figures in physical tests. (See pages 127 and 131.) 

The results of these tests were : 

I day's neat 429 pounds. 

7 days' neat 784 " 

7 days' mortar 209 " 



When analyzed this cement gave 
Insoluble in 10 per cent. HCl 



3.79 per cent. 



Soluble silica 19-43 per cent. 

Alumina and Iron oxide 8.34 " 
Lime 63.44 " 



91 .21 per cent. 



Magnesia trace. 

Sulphuric Oxide SO3 . . 1.89 per cent. 
Volatile at a Red Heat, i . 39 
Undetermined 1.72 " 



5.00 per cent. 



100.00 per cent. 



Active index: 



63-44 

X 19. 43 + 1. 1 X 8.34 



= 1 .00: 



62 

That is to say, we have here a commercial cement that 
consists of 91.21 per cent, cement, 3 per cent, of fuel ash, 0.79 
per cent, of unburned clay, 1.89 per cent, of sulphuric oxide, 
1.39 per cent, of carbonic acid and water, and 1.72 per cent, 
of ingredients not determined. 

This is practically a perfect cement, and the other six 
best American cements so nearly approximated this cement 
in composition that with it they averaged as follows : 

I day's neat 259 pounds. 

7 days' neat 683 '' 

7 days' mortar 257 " 

Insoluble in 10 per cent. HCi 4 38 per cent. 

Soluble Silica. 18.45 per cent. 

Aluminum and Iron oxide. .9.46 " 

Lime 61 .89 " 

89. 80 per cent. 

Magnesia. ... i .78 per cent. 

Sulphuric oxide, SO3 1.87 " 

Volatile at a Red Heat i . 79 '' 

Undertermined 0,38 " 

5.82 per cent. 

100.00 percent. 



. . . , 61.89 

Active index= — ^ -^ =0.997 

2.8 X 18.45 4- I.I X 9.46 ^^^ 



That is to say, these seven American Cements are 89.8 
per cent, pure, with 3 per cent, of fuel ash, 1.38 per cent, 
of unburned clay, 1.78 per cent, of magnesia, 1.87 per cent. 



63 

of sulphuric oxide, 1.79 per cent, of carbonic acid and 
water, and 0.38 per cent, undetermined. 

If a method of analysis can be used that will separate 
this unburned clay and fuel ash from the cement, why 
does it lead to erroneous conclusions ? 

Why should a method be used that makes it impossible 
to distinguish between the silica and alumina in the unburned 
clay and fuel ash, and the iron oxide that can only be dis- 
solved in concentrated hydrochloric acid, and the remainder 
of those ingredients that are properly combined to form 
cement ? 



Further Tests and Proof. 

In order to test these conclusions further, we wrote our 
correspondent and asked him to send us a sample of the 
coal he was using, the mix that was burned and the clinker 
that resulted from the burning. With great kindness, he 
immediately comphed with our request. 

We labeled the samples : 

Coal ". 449b. 

Mix 44QC. 

Clinker . 449d. 

We found the clinker to consist of small nearly spherical 
masses about the size of peas, that had been vitrified and that 
were hard under the pestle and also, larger pieces, that were 
more or less spongy and softer under the pestle. 



64 



449b yielded 11.95 ^.nd 11.76 per cent, of ash, an aver- 
age of 11.85 per cent, which at 400 pounds to the barrel of 
cement, equaled 4.44 pounds to 100 pounds, or 4.44 per cent, 
of ash instead of 3 per cent. Of this ash 22.92 per cent, was 
soluble in 10 per cent. Hydrochloric Acid. 

The Ash consisted of: 

Silica \ . . . 42.94 per cent. 

Alumina and Ferric Oxides 41.41 " 

Lime (CaO) 9-52 

Sulphuric Oxide SO3 , 3.58 

Undetermined 2.55 " 



[00.00 per cent. 



The sulphuric oxide was wholly soluble in dilute Hydro- 
chloric Acid. 



449c contained 19.798 per cent, insoluble in dilute 
Hydrochloric Acid. This insoluble portion contained of 
Silica 68.774 per cent, and Alumina and iron oxide and lime, 
31.226 per cent. These figures are equivalent to 13.62 per 
cent, and 6.17 per cent, of the amount taken. The soluble 
portion contained soluble Silica, 0.17 per cent. ; Alumina and 
iron oxide, 0.60 per cent. ; Lime (CaO), 41.16 per cent. 

These results are equivalent in round numbers to : 

Clay 20 per cent. 

Marl 80 " 



65 
449d when finely pulverized gave : 

Insoluble in lO per cent. 

HCi...,, 4.62 per cent, and 3. 36 per cent. 

Soluble Silica 18.24 *' '' 19.84 " 

Alumina and Ferric Ox- 
ide ... . 8.74 " " 8.65 , '' 

Lime (CaO) 65.64 " " 65.38 

Magnesia (MgO). 

Sulphuric Oxide (SO 3) . . trace trace 



97.24 per cent, and 97.23 per cent. 
Undetermined 2.76 " " 2.77 " 



100.00 per cent. and 100.00 per cent. 



These analyses were made on two separate portions pul- 
verized separately. The insoluble portion did not contain a 
trace of lime. 



449cl. 5.0334 grams of the small unbroken clinker was 
placed in a flask with 250 c.c. of 10 per cent. HCl on March 
15, at 3 P. M. On March 16, at 9 A. M., the action of the acid 
was very marked, each mass was covered with a shell of white 
siHca. On March 18, at 9 A. M., nothing remained of most 
of the spheroids but a white shell of Silica. A few of them 
were but little acted on. On the morning of the 20th the 
residue of Silica was wholly white and the solution had the 
5 



66 

color of proto-chloride of iron. The contents of the flask 
were then analyzed and gave : 

Insoluble Silica 20 . 95 per cent. 

Soluble Silica , 2.09 " 

Alumina and Ferric Oxide 8.43 ** 

Lime , . . 66 . 69 *' 

98. 16 per cent. 



449d. 5.0908 grams of the large porous pieces of clinker 
were placed in a flask with 250 c.c. of 10 per cent. HCl, on 
March 20. The action of the acid was very unequal. Some 
of the pieces were completely decomposed in 48 hours ; 
others apparently containing more iron resisted its action 
for several days. On March 26, one piece was still brown 
and was broken down with difficulty. The contents of the 
flask were then analyzed and gave : 

Insoluble Silica 22 . 01 per cent. 

Soluble Silica with trace of iron 1.56 " 

Alumina and Ferric Oxide 8 . 97 " 

Lime *.... 66.72 *' 

99.26 per cent. 



These results show that our correspondent was mistaken 
in assuming that {y) 

*' the best Portland cements are thoroughly homoge- 
" neous in character," 

as his own clinker is not homogeneous. Moreover, these 
analyses prove beyond question that the results of the action 



&7 

of acid out of the same bottle and acting on material from 
the same bottle depends upon the size of the masses of 
cement. The two samples of clinker above set forth were 
purposely ground of different degrees of fineness. 

We then asked our correspondent to send us samples of 
coal, mix, clinker and ground cement, that would be as 
nearly as possible representative of the same batch of mix. 
These were received by us and numbered 

Coal 449 E. 

Clinker 449 D. 

Mix ... 449 C. 

Cement 449 B. 



449 E yielded 10.63 P^r cent of ash, which is equal to 
3.99 per cent, of ash in the clinker. When analyzed this ash 
yielded : 

Silica . . , 43-30 per cent. 

Alumina and Ferric Oxide 38.69 '* 

Lime 9.12 '' 

91 . II per cent. 



There was undetermined SO-3, CO 3 and a trace of HgS. 

This analysis, as well as 449b, seems to indicate that the 
lime in the fuel ash combines to form a soluble compound 
with a part of the silica, alumina and iron, while the re- 
mainder of the silica, alumina and iron, being in excess, still 
continues in combination in a form not readily decomposed 



68 

by dilute acids, although easily attacked by concentrated 
acids. 

This explains why some of the very best cements are 
gelatinized with only a little more than a trace of matter un- 
decomposed by concentrated acids and yield a residue to 
dilute acid having the appearance of ashes, but containing no 
lime, and less in amount than the ash contained in the coal 
used, as is shown in the analytical results given above. 



449 D. The clinker was finely pulverized. 

It contained a trace of SO3 and no MgO. 

Analyzed it gave : 

Insoluble in 10 per cent. HCl 2.81 per cent« 

Soluble Silica 20 . 61 *' 

Alumina and Ferric Oxide 8.69 ^' 

Lime c 65 . 62 *•' 



97 . 73 per cent. 



449 C gave on analysis : 

Silica 14 , 62 per cent. 

Alumina and Ferric Oxide 9.21 *' 

Lime 4f05 " 



The clay had absorbed some water. This mix is slightly 
different from the first, containing a little more clay. 



69 

449 B. The Physical Tests were : 

I day neat 369 pounds. 

7 days neat 720 " 

28 days neat 756 " 

7 days mortar 209 " 

28 days mortar 326 '^ 

The cement was analyzed as usual. It gave : 

Per Cent. Per Cent. 

Insoluble in 10 per cent. HCl.... .... 3-73" 

Soluble SiHca 19.65 Per Cent. 

Alumina and Ferric Oxide 7*95 [ 



Lime (CaO). , 64.27 

91.87 J 

Sulphuric Oxide (SO3) 1.54 

Magnesia (MgO). 

Volatile at a red heat 3. 1 1 



465 



100.25 percent. 



64.27 

Active Index= -—5 TTT^r. — ^ ; ;r^7: = 1.008 

2.8 X 19.65 4- I.I X 7.95 



This sample when analyzed by Humphrey's method 
gave: 

Silica 22.36 per cent. ~] 

I 
Alumina and Ferric Oxide 7.52 " )- 95.92 per cent. 

Lime 66.04 " J 



^o 



AN OBJECT LESSON. 



449 F. A mixture of pulverized fire-brick and lime 
was made, having approximately the ultimate compo- 
sition of a Portland cement. 



When analyzed by our method the results were as fol- 
lows : 



Insoluble in lO per cent. 

HCl 33.25 per cent 

Soluble Silica .11 '* 

Alumina and Ferric 

Oxide 28 

Lime 60.89 " J 



94.53 per cent. 



The insoluble portion contained : 

Silica 58. 52 per cent. 19.45 per cent, of whole 

Alumina and Ferric 

Oxide 29.98 '' 8.97 " 

Lime 11.98 " 3.98 



32.40 " '' 

Magnesia undetermined. 

Analyzed by Humphrey's method it gave : 

Silica 19.82 per cent. ] 

Alumina and Ferric Oxide 8.68 " h 94-94 per cent. 

Lime 66.44 'V J 

Magnesia undetermined. 



Humphrey's method is not a proper method of mineral 
analysis : 

Whatever portion of the material is soluble should be 
dissolved without fusion. Fusion in the manner described 
introduces a large amount of sodium chloride into the assay 
to no purpose, and should therefore be avoided. So much 
sodium chloride makes it difficult to separate the silica com- 
pletely, and prolongs the scheme to no purpose. More- 
over, the results given above speak for themselves. 



Our Method of Analysis. 

Believing that the results obtained by the method of 
analysis used by ourselves, and the interpretation of which 
they are capable, furnish the strongest possible argument for 
its general use, we submit the following suggestions respect- 
ing it. 

First — That the samples should be taken and preserved in 
a well stoppered bottle. 

Second — That the sample for analysis should be ex- 
actly like the sample submitted to physical tests. It 
should be subjected to no treatment whatsoever that 
will change its properties in any manner. It should be 
neither dried nor pulverized. 

Third — That five grams should be weighed out and 
gradually introduced into 250 c.c, of not stronger than 10 
per cent. HCi, in such a manner as to avoid any appreciable 
rise in temperature. The solution should be vigorously 
stirred at intervals for half an hour. Portland cements of 



72 

good quality do not effervesce. If effervescence follows it 
indicates the presence of carbonic acid. Traces of HgS are 
to be expected. A black residue indicates carbon or soot, 
which may be estimated by gathering the residue on a 
balanced filter, weighing, burning off the carbon and again 
weighing. 

Our correspondent regards this residue as the coarse 
particles of the cement deprived of lime by "local separa- 
tion," whatever that may mean. There is not a particle of 
evidence to support any such contention. The residue from 
lo per cent. HCl is not coarse. It is fine as ashes, and is 
ashes. He says that it is not safe to add to the raw material 
lime enough to convert the silica and alumina of this fuel 
ash into cement, hence it is properly to be inferred that the 
lime and ash will not unite to form cement. That being the 
case, the cement is dissolved away from the ash and un- 
burned clay, the former of which can only be brought into 
solution by prolonged action of the acid on the material in 
very fine powder. To us, this means which we have dis- 
covered of separating the cement from that which is not 
cement, seems extremely fortunate, and we cannot under- 
stand why anyone else who desires to distinguish between 
good and bad cements should think differently. 

Fourth — That the filtered solution is evaporated to dry- 
ness over a water bath, the residue carefully and completely 
desiccated, drenched with concentrated HCl, warmed, taken 
up in water, the silica filtered off, dried and ignited as 
"soluble silica." This is a proper designation to be applied 
to this material, as it has been wholly dissolved in the action 
of the weak acid upon the cement. It is also the silica that 
is in combination to form cement, if not augmented by the 
silica that forms the bulk of the fuel ash, and, in Humphrey's 
scheme, also by the silica of the unburned clay. 

Fifth — That the filtrate from the silica is made up in a 
graduated flask to I litre, and two portions of lOO c.c. 



73 

each, are precipitated with ammonium hydrate, the ammonia 
boiled off and the precipitate brought upon a filter and 
filtered while hot. Mr. Humphrey very properly dissolves 
this precipitate in dilute HCl and reprecipitates, passing the 
filtrate through the same filter. In no other way can the 
iron and alumina be freed from lime and magnesia, if either 
exists in considerable quantity. 

Sixth — That the united filtrates are brought to a temper- 
ature near boiling and the lime precipitated as oxalate. 
After being allowed a sufficient time to settle, the lime may 
be filtered off and determined either as oxide or carbonate, 
or titrated with potassium permanganate, as suits the con- 
venience of the operator. It is well to follow Mr. Humphrey 
and redissolve and reprecipitate the lime in presence of 
magnesia. 

Seventh — That if extreme accuracy is required, the fil- 
trate from the lime will be evaporated to dryness, ammonium 
salts expelled, and the magnesium precipitated with hydro- 
ammonium-phosphate. For practical purposes this evapora- 
tion is not necessary, but the magnesia may be determined 
in the filtrate from the lime. 

Eighth — That for practical purposes too, the sulphuric 
oxide may be determined in the filtrate from the magnesia, 
after it has acidulated, but the original solution is better. 
To test this point, the sulphuric oxide was determined, {a) 
in the original hydrochloric acid solution of a cement freed 
from silica, {b) in the same solution from which the iron and 
alumina had been precipitated, (c) in the same solution from 
which the iron and alumina had been precipitated and the 
ammonia had been boiled off, {d) from the solution after 
magnesia. The determinations (a) and {c) varied by 0.03 of 
I per cent., {d) was yL of I per cent, greater, while (b) was 
very much less than ether of them. According to our 
experience barium sulphate thrown down in presence of iron 
and alumina always contains traces of these oxides. 



74 



Our Conclusions. 

With the determination of the matter volatile at a red 
heat, these results furnish all of the analytical data necessary 
to form a judgment concerning the quality of any cement^ 
either Portland or Rosendale, and with slight modifications 
the method may be applied to concretes. 

To cast these results into the form of an " Active Index," 
or " Inactive Constituents," will not change the results in 
any respect, but may be useful in comparisons, as are many 
other wholly artificial devices. 

It was originally our purpose to discuss the significance 
of results obtained by us in the determination of the lime 
and alumina of cements soluble in water, both gravimetri- 
cally and by titration, but the length of this report leads us 
to defer this matter till another occasion. 

Respectfully submitted. 

Otto H. Klein, 

Chief Engineer, 
S. F. Peckham, 

Chemist. 



Exhibits 

"A." 



n 

Exhibit " A." 

Dr. Charles F. McKenna's Letter. 

ioi) " Sir — The article which appeared in your issue of the 
'* 4th inst, under the title * Relations between Physical and 
'■*' * Chemical Tests of Cement ', being an abridgement of the 
*' Report of Otto H. Klein and S. F. Peckham to the Com- 
*' missioners of Accounts of New York City, contains so 
" many egregious misconceptions of the role of chemistry in 
** the technology of Portland cement, so many contradictory 
*' passages and so much ignorance of cement manufacturing 
*' processes, as to make the judicious grieve and cause an 
"■ emphatic protest against allowing such work to be ac- 
*' cepted abroad as representative of the depth of American 
'' knowledge of the chemistry and technology of cements. 
'' A protest is needed for the further and more important 
" reason that the evils, which have resulted in this country 
*' from a misunderstanding of the methods and their tech- 
*' nique and purpose recommended in the physical testing 
'* of cement, bid fair, with such a publication as this having 
** a vogue, to bring into the field of the chemical study of 
** cement a still longer train of false notions, bad methods, 
'* encouragement of fraud, discouragement of honesty and 
" really serious consequences to the engineering profession." 

{b) " The editorial comments upon that report in your 
** same issue pointed out a few of the absurdities of this 
" laborious production, as, for instance, inviting manufac- 
" turers and importers to furnish the * average sample,' and 
" the crudeness or freshness exhibited in the treatment and 
'* conduct of the work by the Commissioners and their 
*' experts." 



78 

(c) " According to the authors, the object of this re- 
** search was to ascertain ' what relation, if any, exists be- 
'* ' tween the results obtained by physical tests and chemical 
'* * analyses of cements.' In looking for the answer to this 
" throughout the report and in the summing up, we find * no 
** * such correspondence was revealed in any case and the 
*^ * results were apparently without relation.' Nevertheless 
" they are later and very fully discussed as if such a relation 
^* had been proven." 

(d) •* We find that the chemist states that he had had a 
** large experience in cements, cement clays and limestones, 
*^ but not in Portland cements, that this was supplemented 
** by a careful examination of the last edition of * Crooke's 
" ^ Select Methods of Chemical Analysis,' that the result was 
'* the practical adoption of Stillman's method and when this 
*' was abandoned his own method was adopted. It is a pity 
*^ that he has overlooked such excellent articles on this branch 
" of the subject as those contained in the treatise of Schoch 
" and that of Candlot, but apart from this his method is 
" genuinely unique in the annals of analytical chemistry and 
'* some of the conclusions which he has been led to in dis- 
*' cussing analyses made by it are absurd." 

(e) *' In the first place, he misuses the well understood 
" term ' soluble silica,' and applies it to that portion only of 
" silica which goes into solution in 20 per cent, hydrochloric 
'' acid, ignoring any silica of silicates insoluble in such. 
'* Now, in mineralogical chemistry, and in all analytical 
*' chemistry for that matter, ^ soluble silica ' is both the 
'* silica soluble in acid plus the forms of silica soluble in soda 
" carbonate solution subsequently applied. It may be that 
" this residue may not generally be of great value in a 



79 

^' cement, but no one is justified in so asserting in any par- 
" ticular case, and above all in misusing the term in a way 
" that will render results useless for comparison with the 
*' best practice in this country and in Europe." 

(/) " He uses 5 grams throughout the analysis, without 
*' subdividing, and in a cement with 60 per cent, lime he 
" succeeds in determining the lime by ignition of the oxalate 
*' to constant weight. Most chemists would think this a 
" difficult achievement since the bulk and surface of this 
'•' precipitate will be so large as to be very favorable to the 
^' considerable absorption of moisture by the caustic lime." 

(g) " It appears that in presenting his experiments the 
" chemist was interested in seeing how the method of 
" adding acid to the sample of cement, or vice versa, 
*' affected the results he obtained in percentage of lime in a 
*' given sample. He gives the astonishing figures 55.05, 
'' 62.32, 62.74, 61.76, and 61.72 per cent, all obtained on the 
*' same sample, and the differences to be ascribed to the 
*' difference in manipulation mentioned. One can under- 
'' stand how the amount of siHca going into solution would 
'' differ, but why analyses of the same sample of cement 
^' should give these varying percentages of the total of one 
*' constituent is beyond my comprehension." 

{k) " He says that ' the determination of the carbonic 
' acid involved a large amount of work of questionable 
' practicable utiUty, as after a number of very careful deter- 

* minationsit was found that the carbonic acid found was in 

* every case a small percentage less than the amount vola- 
' tile at a red heat. This latter determination was made by 
' heating i gram in a small covered platinum crucible to 
' a constant weight.' Few chemists would accede to this 



8o 

*' and none would of those who have had experience with 
'' the cements that are offered engineers to-day. And it 
*' does not agree with his own results, as he mentions No. 30 
'* giving 12 per cent, carbonic acid, while his analytical table 
*' (not included wholly in your text, but issued in a blue 
*' print at the meeting of the Society of Chemical Industry 
" at which the paper was presented) shows that the amount 
" volatile at a red heat on this sample was 17.92 per cent, 
*' No. 58 gave 28.86 per cent, volatile matter and he does not 
" class it with those adulterated with carbonate of lime, dis- 
" cussed elsewhere in his paper, but says of it : No. 58 is a 
*' poor cement all through, being low in lime, high in mag- 
" nesia, with nearly one per cent, of carbon, and showing by 
" the loss at the red heat of 28.86 per cent., either the effects 
*' of ageing or bad or insufficient burning. It is a very bad 
" cement." 

(i) "The carbon he finds he ascribes in all cases to un- 
'' burned coal, even though it is quite likely that many of the 
" cements which he examined had been burned in rotary 
" kilns using oil fuel. He does not seem to know that at 
" times some manufacturers purposely grind a small portion 
" of coal with the clinker." 

(k) " His determination of lime and alumina soluble in 
" water was rightly called important, probably more impor- 
" tant than he seems to think, but he does not mention the 
" valuable and simpler standard alkali metric test of a water 
" solution of 0.5 gram of cement with decinormal acid. 
" In fact, how unique this experimenter is in his chemical 
" work may be infinitely clear to engineers familiar with 
" physical testing when they read how he adds together all 
" the figures for tensile strength at different periods and uses 
" the sum as a means of classification." 



8r 

(/) "As to his use and misuse of the term 'active index,' 
" I will only say this : The active index is only one of many 
•* interrelations of composition and character which are used 
*' for diagnosis and which are to be credited with more or 
" less weight. It is a figure which should be delicately 
" touched upon, which has been derived from more or less 
" uncertain assumptions of the presence of the bases and 
" acids in certain definite combinations and which assuredly 
" cannot be adopted for judgment of a cement which has 
" been analyzed according to such a method as we find here. 
" At least, the adulterants should be ascertained to exist in 
" a certain form in a cement before gray matter is wasted 
" over ' active index.' " 

" {m) " But what shall be said of the attempt here made to 
'' apply the theoretical formula for pure Portland cements to 
" natural cements. This is so shockingly absurd, so demon- 
" strative of an ignorance of the very nature of hydraulic 
" action and of the character of the various hydrauhc mate- 
" rials, that nothing need be said further than to quote him 
" Avhere, applying Newberry's formula to Rosendale cements, 
" he says : ' In general also they exhibited the effects of 
" 'both under and over burning.' 

(n) " Apologizing for the taking of so much space in your 
" columns, I will close with the statement that there is much 
*' other similarly interesting material in this report and that 
" I have tried to set down here nothing that would be unfair 
" to the authors of it, while yet justifying my assertion that 
'* its publication is a wrong to American chemical and engi- 
" neering practice." 

" Very truly yours, 

" (Signed) Chas. F. McKenna." 

6 



82 



Exhibit "B/' 

Editorial Criticism of Engineering Record 
Quoted by Mr. Lewis. 

" As a matter of fact the main criticisms which may be 
" made on the report can be based on a certain kind of crude- 
" ness or freshness exhibited in the treatment and conduct 
*^ of the work by the Commissioners of Accounts and their 
" experts. It may even be doubted whether all the positions 
" taken by them can be successfully defended. They have 
" made investigations of value to The City of New York, 
" and their efforts and purposes are to be commended, but 
** some of their operations should have been conducted in a 
" different manner ^ * ^ Again, the rather sweeping 
" rejection of the prevailing methods of chemical analysis of 
" cements in this country and of Europe is at least open to 
'* some question." 



83 



Exhibit "C." 

Quotations from 

Eleven Page Answering Report, 

Dated January 4, 1901, 

MADE BY 

Engineer of the Department of Highways, 

Borough of Brooklyn, 

on 

Watkins Street Regulating and Paving Contract. 

After showing that the physical tests appHed to the 
cement in question gave results that were quite variable, but 
averaging above the required strength for Rosendale cements, 
he proceeds : 

I. " Chemical analyses have been made of the 
" samples taken on October 23, and on November 5, in 
" order to compare them with those obtained by 
" Professor Peckham, and given in his report marked 
" Exhibit ^'A," 

" These analyses showed the following composition : 



Carbon 

Matter insoluble in lo per cent. HCi 

Magnesia 

Sulphuric Oxide 

Matter volatile at Red Heat 

Inert constituents 

Soluble silica 

Alumina and Iron Oxides 

Calcium oxide (lime) 



Sample of 
October 23. 


Sample of 
November 25. 


.985 


1.022 


9.486 


13.277 


2.843 


2.861 


.760 


•759 


13-369 


14.972 


27-443 


32.891 


14.741 


13.128 


5.728 


5-439 


52.102 


48.520 



99.978 



84 

2. " It will be noticed that the most conspicuous 
" difference between the above analysis and that of 
" Professor Peckham is in the larger percentage of 
" matter insoluble in lO per cent, hydrochloric acid, and 
" in the materially larger per cent, of lime in our two 
" samples. 

3. " The report received from our Chemical Labora- 
" tory with these analyses, states as follows : 

" As will be seen above, the percentages of siHca, 
" alumina and iron oxides and lime (which are the 
" active hydraulic ingredients of a cement) are obtained 
" by decomposing the silicates, aluminates, etc., of the 
" cement with 10 per cent. Dilute Hydrochloric acid. 
" Admitting for the sake of argument that the percent- 
" ages of silica, alumina and ferric oxides, and lime, so 
" obtained represent the maximum percentages of active 
" hydraulic ingredients, the only conclusion that we can 
" draw is, that these analyses show a cement in which 
" the active hydraulic ingredients are admirably well 
" balanced. The percentage of inert constituents is 
" very low, as shown by comparison with the average 
" Rosendale Cement analysis in the report of The 
" Commissioners of Accounts of May 24, 1900. The 
" averages of the percentages of inert constituents of 
" Rosendale Cements is 40.22 per cent." 

4. " We however believe that the above method of 
'* analysis to be a new, radical and arbitrary one, and at 
" variance with the usual practice, which is to employ 
" concentrated \vy^xo(i\Aox\c acid, and determining all of 
" the silica, alumina, and iron oxides, and lime so 



85 

" decomposed from the silicates, aluminates, etc. This 
" method has given entire satisfaction in the past, and 
" Ave see no reason tor discarding it." 

5. "In using concentrated hydrochloric acid, the un- 
" decomposed silicates, etc., are reduced from 9.5 to 2.3 
" per cent, and from 13.3 to 3.8 per cent., while the solu- 
" ble silica is increased from 14.7 to 19.6 per cent., and 
" from 1 3. 1 to 20 per cent., and the lim.e is increased a 
" little over i per cent. The report of our chemist, Mr. 
" Broadhurst, then proceeds as follows : 

" It has never been claimed, that Rosendale (nat- 
" ural) cements contain ingredients in such proportions 
'" as to make a theoretically perfect cement. While 
" chemical analysis is an invaluable aid in determining 
" deleterious matter and the cause of disintegration of 
'' cements, there are certain combinations due entirely to 
" the method of burning, which render a cement valuable 
'• or worthless, as shown by physical tests and which 
" chemical analysis fails to indicate." 

* 6. " We consider this Commercial Rosendale Ce- 
" ment to be a very superior one for the following rea- 
" sons : 

" Comparatively small percentage of inert 
constituents ; 

" Low percentage of magnesia ; 

" Low percentage of sulphuric Oxide ; 

" Soundness as shown by the boihng test ; 

'' Great ultimate tensile strength." 



86 

7. " The Commissioners of Accounts claim that the 
*' conclusions drawn from tests and analyses made of the 
'* sample of cement were confirmed by chemical 
** analyses, made of some of the concrete taken from the 
" street on November 28, 1900, by Mr. Creuzbaur, 
" representing the Department of Finance, and Messrs. 
** Klein and Dusenberry, representing the Commission- 
" ers of Accounts." 

8. *' The manner in which these so-called samples 
' were taken, the analyses that were made of the mortar 
' and the comparison of the results obtained with a 
' purely hypothetical standard, are such as to render 
' their conclusions entirely valueless. The concrete on 
' the street in two small spaces, each one foot or less in 
' diameter was broken up. The loose material con- 
' sisting of stone and mortar, was scooped out. The 
' material from each of the holes was then divided into 
' two parts, one part of each being taken to the Chemist 
' of The Commissioners of Accounts for Analysis. In 
' the report (Exhibit " B ") it is stated that they ' were 
* ' brought in boxes ' and ' the lumps of stone were 
' ' loose in the sand and cement.' A portion of the 
* material was poured from each box and the 
' stone was separated from the fine material. In 
' the case of one portion examined the stone 
' weighed 360 grams, and in the other case 547 
' grams, and it would appear as though the chemist 

' had first intended to examine the concrete as a whole, 
' but he subsequently confined his investigations to 
' the mortar only. This mortar was treated with dilute 
' hydrochloric acid, and from the result of the analyses 
' it is found that one sample contained 22 per cent, and 



87 

'' another 19.5 per cent of active matter. These results 
" are then compared with the amount of active matter 
" which should be found in a mortar made of one part 
" of cement, containing 15 per cent, of inert matter, and 
" two parts of sand. Their attention is called to the 
" fact that the analysis of the Standard Rosendale 
^' cements furnished by the viaiiufactiirers as de- 
" scribed in the report of the Commissioners of 
" Accounts of May 24, 1900, contained about 46 per 
" cent, of inert matter, and the ordinary run of Com- 
.'• mercial Rosendale cement contains about 30 per cent. 
" of inert matter, the absurdity of comparing the re- 
"■ suits obtained from an analysis of the mortar found 
" on Watkins Street with a hypothetical Rosendale 
'' cement containing only 15 per cent, of inert matter 
" is so apparent as to need no comment." 

9. " In order to make a fair examination of the con- 
' Crete, the asphalt pavement was opened in two places 
' on December 29, 1900, one opening about two feet 
' square being made in about the middle of the block 
' between Sutter and Blake avenues, and one about 
' four feet square in the block between Blake and 
* Dumont avenues. These openings were made in the 
' presence of Mr. R. W. Creuzbaur, Principal Assistant 
' Engineer of the Department of Finance, Mr. George 
' W. Tillson, Principal Assistant Engineer of this 
' Department and myself Upon removing the asphalt, 
' the concrete was in both cases found to be in good 
' condition, firm, dense, and while not, of course, as 
' hard as would have been a concrete made of Portland 
'* cement, it was in the condition to have been expected 
" of concrete made of good natural cement. It resisted 



88 



the blows of a pick until the mass was shattered, when 
it could readily be broken. In the second opening a 
large unbroken slab of concrete was cut out. Two 
portions of this were brought to this office, one of 
them for Mr. Creuzbaur and the other in order that 
a fair separation of the stone and mortar could be 
made from a piece large enough to furnish some indi- 
cation as to the manner in which the concrete was 
mixed. The results of this examination conducted 
by Mr. W. H. Broadhurst, Chemist of this Depart- 
ment, along the lines described in the report of 
Professor Peckham, known as Exhibit ' B,' were as 
follows : 



** Sample H59 weighed 1,059.09 grams, of which 
" 668.50 grams were stone and 390.59 were mortar. 
" Sample H60 weighed 3,794.05 grams, of which 2,563.95 
*' grams were stone and 1,230.10 grams were mortar." 

10. " Mr. Broadhurst's report continues as follows : 



Insoluble Matter. 
Sand and other mineral matter. ... 

* " So-called " carbon 

Soluble Matter. 

Silica 

Alumina and Iron Oxides 

Lime 

Magnesia 

Sulphuric Oxde 



Sample H59. Sample H60. 



71.180 per cent. 
•703 



883 per cent. 

620 per cent. 
846 " 
780 

Trace 

Trace. 



92.129 per cent. 



71.342 per cent. 
•831 " 



72.173 percent. 

3.461 per cent. 
2.810 
13.462 
Trace. 
Trace. 



91.906 per cent. 



* *' Insoluble matter volatile on ignition.' 



89 

" We find only a trace of iron insoluble in con- 
*' centrated hydrochloric acid, there is hence none 
" rendered inert by burning." 

11. "A mortar made of one part of Rosendale ce- 
" ment and two parts of sand by volume is equivalent 
" to 28.67 parts of cement to 71.33 parts of sand by 
" weight (computed from results given in Annual Re- 
" port of Chief of Engineers, U. S. A., 1894, page 
" 2313). I cubic yard of mortar — 2.75 bbls. of cement 
" of 300 lbs. per bbl. (80 lbs. per cubic foot). ."]() cubic 
" yards of sand, 100 lbs. per cubic foot." 

12. " This Commercial Rosendale cement contains 
" approximately 30 per cent, of so-called ' Inert Mat- 
'* ter' (Matter insoluble in 10 per cent. Dilute Hydro- 
" chloric acid). We do not know of any Rosendale 
" cement which contains 15 per cent, of matter cor- 
" responding to this figure." 

" By weight, therefore, 100 parts of mortar would 
" contain 71.33 parts of sand and 8.60 parts of so-called 
" inactive cement, equivalent to 79.93 parts of inert 
" matter and 20.07 parts of active matter." 

" The above analyses show that sample H59 con- 
" tains 20.246 parts of active matter, and sample H60 
" 19-733 parts of active matter, in 100 parts of mortar, 
" corresponding almost exactly with the proportions of 
" sand and cement required by the specifications." 

13. " The results which I have given you of tests 
" which have been carefully made demonstrate, I think, 
" beyond a doubt that the concrete on Watkins Street 



90 

" was laid in accordance with the specifications, and the 
" results are satisfactory. You will note that the con- 
'' elusions drawn by our chemist are based largely upon 
'' premises laid down by the Commissioners of Ac- 
'' counts themselves, although it is not admitted that 
'* these premises are sound. The whole theory of their 
'' investigations of Rosendale cements being carried 
'* along the same lines as are investigations of Portland 
*' cements is certainly untenable. To show that this 
" Department is not alone in this opinion, I beg to 
" refer to the editorial comment on the miuch-advertised 
*' report of theCommissioners of Accounts of May 24, 
" 1900, which is contained in the Engineering Record 
" of- August 4, and which says : 



91 



Exhibit " D." 



Quoted and Discussed as Exhibit " A " in the Let- 
ter OF Mr. Lewis. 



New York, N. Y., December 7, 1900. 

Otto H. Klein, Esq., Chief Engi7ieer, 

Commissioners of Accounts, New York : 

My Dear Sir — Concerning the sample of cement 
marked No. 279, I have to report as follows : 

14. The reaction indicated a cement that was badly 
burned. The finest ground portion that went through the 
sieve first did not effervesce ; but the coarser particles that 
went through the sieve last and some coarse fragments that 
did not go through a No. 40 sieve at all, effervesced like 
fresh lijiiestone. The portion insoluble in 10 per cent, 
hydrochloric acid contained a considerable amount of grains 
of quartz sand and insoluble oxide of iron, indicating that 
some portion of the cement was overburned and that there 
was not the necessary care taken in the manufacture 
to exclude the inert sand that helped swell the proportion 
of the inactive ingredients to very near one-third the whole 
amount of the cement. 



92 

Of these inert constituents there was : 

Carbon ,. ,,..._ o. 182 per cent. 

Matter insoluble in 10 per cent. HCi 16.738 '' 

Magnesia 2 . 300 " 

Matter volatile at a red heat 13 . 170 " 

32.390 percent. 

Of the active ingredients, there were : 

Soluble Silica , 1 5 . 065 per cent. 

Alumina and Iron Oxides. 6.970 '* 

Calcium oxide (lime) 45 . 540 " 

32.390 

99.965 per cent. 



15. At least 12 per cent, of the inert matter volatile at a 
red heat is carbonic acid, which in the cement is in combina- 
tion with a part of the lime as wholly inert carbonate of lime, 
amounting to 27.276 per cent. Deducting the 15.276 per 
cent, of lime in this inert combination from the 45.54 per 
cent, of lime found, there remains only 30.264 per cent, of 
active lime, which is just about one-half the amount 
required for a good cement. When such a cement as this 
is mixed with two parts sand, the one-half part of cement 
that it really contains is mixed with four half parts of inert 
matter in addition to the one-half part that is already 
there, making five half parts to one-half part or a proportion 
of one to five instead of one to two. It is no wonder that 
a concrete made from such cement is worthless. 

16. The active index of this cement is 0.913, showing too 
little lime if it was all active. The actual amount of active 
lime present would show a still smaller fraction. 



93 

The following is an exhibit of the results of the analysis : 

Carbon o . 1 82 per cent. 

Insoluble matter 16 . 738 

Soluble silica 15. 065 

Alumina and Iron oxides 6.970 

Calcium Oxide (lime) , 45 . 540 

Magnesia 2 . 300 

Sulphuric Oxide . . . , trace. 

Matter volatile at a red heat 1 3 . 1 70 



99.965 per cent. 



Active Index 0.913 

Inactive Index , , 32 . 39 



Respectfully submitted. 

(Signed) S. F. Peckham, 

Chemist. 



94 



Exhibit " E. 



Quoted and Discussed as Exhibit '' B " in the 
Letter of Mr. Lewis. 



New York, N. Y., December 3, 1900. 

Otto H. Klein, Esq., Chief Engineer, 

Commissioners of Accounts, New York City : 

My Dear Sir — Concerning the two samples of Concrete 
taken from Watkins Street marked No. 280A and No. 280B, 
I have to report as follows : 

17. The two samples were brought in boxes. The lumps 
of stone were loose in the sand and cement. A portion was 
poured from the boxes'and air dried. When dried they were 
sifted through a No. 10 sieve. Nearly all of the cement and 
sand was in this way separated from the stone. The few 
lumps that were coherent were easily broken up between 
the fingers and a complete separation made from all but a 
very few small fragments of stone that passed the sieve. 

18. When air dry, the stone in No. 280A weighed 360 
grams and the sand and cement 235 grams. In round num- 
bers 60 per cent, and 40 per cent, respectively. 

When air dry, the stone in No. 280B weighed 547 grams 
and the sand and cement 285 grams. In round numbers 65 
per cent, and 35 per cent, respectively. 



95 

19- The two samples were analyzed air dry, as if they 
had been cement, the material separated from the stone being 
in the form of a coarse powder. 

Ten grams of each sample were taken. When introduced 
into dilute hydrochloric acid both samples effervesced freely 
from escape of carbonic acid gas. The matter insoluble in 
the acid consisted of: 





280A. 


280B. 




69.604 per cent. 
•521 


71.353 per cent. 
.632 " 


Carbon 




Total 


7c. 125 per cent. 

3.685 per cent. 

5. 855 
12.440 

Trace. 


71.985 per cent. 

3.385 per cent. 
3-565 
12.590 

Trace. 


The soluble matter consisted of : 

Soluble silica 

Alutnina and Iron Oxides • 


I ime . 


Magnesia 








92.105 per cent. 


91.525 per cent. 



There was a large percentage of iron in the insoluble 
residue that was rendered inert by burning. 



20. A concrete made of one part Rosendale cement, 
containing 15 per cent, of inert matter, and two parts sand, 
would contain 215 parts of inert matter in 300 or about 71 
per cent. The remaining 29 per cent, should consist of 
cement ; that is of soluble silica, alumina and iron and lime, 
in proper proportions. In these samples there is 22 per 
cent, in No. 280A and 19.5 per cent, in No. 280B. There is 



96 

not lime enough to form a hydraulic compound with the 
soluble silica and alumina and iron in either, provided the 
cement was thoroughly burned and all of the lime chemically 
active ; but, a large part of the lime is unburned, as indicated 
by the escape of a large quantity of carbonic acid gas, and 
consequently a large part of the lime is inert and not in an 
active form. 

In other words, there is not cement enough in the 
concrete to hold the concrete together, hence the un- 
satisfactory condition of the concrete now, in conse- 
quence of a lack of and a condition of ingredients that 
no amount of ageing can remedy. 

Respectfully submitted, 

(Signed) S..F. Peckham, 

Chemist. 



COMPARISON BETWEEN 
PHYSICAL TESTS AND CHEMICAL ANALYSES 

OF 34 SAMPLES 

OF PORTLAND AND ROSENDALE CEMENTS, 

WITH THREE TABLES OF RESULTS. 



REPORT 



Hon. ROBERT A. VAN VVYCK, Mayor, 



JOHN C. HERTLE, 

EDWARD OWEN, 

Commissioners of Accounts of tlie City of New York, 

riAY 24, 1900, 

And read before the New York Section of the Society of Chemical 
Industry of England, May 25, 1900. 



99 



LETTER OF TRANSMISSION. 



Office of the Commissioners of Accounts, 
Stewart Building, No. 280 Broadway, 

New York, May 24, 1900. 



Subject — Comparison Between Physical Tests and Chem- 
ical Analyses of Portland and Rosendale 
Cements. 



Hon. Robert A. Van Wyck, Mayor ; 

Dear Sir — " The Commissioners of Accounts of the 
City of New York '' beg to submit herewith for your con- 
sideration a report dated May 21, 1900, made to them hy 
Mr. Otto H. Klein, their Chief Engineer, and Professor S. 
F. Peckham, Chemist in charge of their Laboratory. 

This report is the product of much labor on the part of 
these two officials, frequently extending beyond their usual 
hours during the period between the 26th day of May, 1899, 
and the present date, and embodies the physical tests and 
results of chemical analyses made of the following samples 
of cement : 

'' Samples. 

Domestic Portland, obtained from manufacturers. . 17 
Imported Portland, obtained from agents 2 

19 

Rosendale, obtained from manufacturers 13 

Rosendale, obtained from City Works in course of 

construction 2 

15 

Total number of samples 34 



100 

These samples were obtained by us in reply to letters sent 
by this office, one of which we copy as follows : 

" New York, May 26, 1899. 
" Gen'TLEMEN — Will you be kind enough to sead us, within the next 
" week, a twenty-five pound sample of your fresh-ground Portland 
" cement, the same to be used for a comparative test as a record in this 
" Department. 

" Respectfully, 

(Signed), ** John C. Hertle, 

'• Edward Owen, 
" Commissioners of Accounts.^' 

In the course of our examinations of the various contracts 
with the City, for regulating, grading and paving, during the 
years 1898 and 1899, your Honor will no doubt recollect the 
numerous reports made by us of the poor quality of cement 
used in concrete foundations for roadways, which finally cul- 
minated in our recommending, in a report dated May 4, 1899, 
the exclusive use of Portland cements, from which report we 

quote as follows, viz. : 

" New York, May 4, 1899. 
*' Hon. Robert A. Van Wyck, Mayor : 

*' Dear Sir — We beg to call your attention to the accompanying 
" cement test sheet, which shows that the Rosendale cement used in the 
" concrete foundation for asphalt blocks does not come up to the require- 
" ments of a good, serviceable cement, * * * 

" The concrete foundations for pavements made of Rosendale cements 
*' in this city have, of late, given reasons for numerous complaints, criti- 
" cisms and legal actions. 

" We believe it would be in the interest of the Department of High- 
'* ways, and of the Corporation Counsel, if the use of Rosendale or nat- 
'• ural cements for foundations of pavements in this city would be 
" excluded from the specifications in the future, and that only the freshly 
" ground American Portland cements be permitted to be used. 

" The concrete made thereof should be composed of one part of Port- 
" land cement to three parts of sand to seven parts of broken stone, the 
" stone to be of such a size as to pass through a two and one-half inch 
" ring in any direction. 

" There is very little difference in the cost of concrete foundations, 
" whether made of Rosendale or of Portland cements, but too much 
'* stress cannot be laid on the advantage derived from the use of Portland 
*' cement concrete for the foundation of pavements. 
" Respectfully submitted, 

(Signed), " John C. Hertle, 

" Edward Owen, 
" Commissioners of Accounts.''^ 



lOI 

On October i6, 1899, we made an additional report, 
recommending the substitution of Portland for Rosendale 
cement, and in said report called attention to the fact that 
our conclusion was also shared by the Engineers of the 
Comptroller's office, as is shown by the following quotation, 
viz. : 

*' New York, October 16, 1899. 
" //on. Robert A. Van Wyck, Mayor: 

" Dear Sir — The former specifications made up by the Department of 
" Highways for asphalt pavements on concrete foundations, for all the 
" boroughs, permit the em.ployment of both Portland and Rosendale 
" cements in the concrete foundation. 

" On account of the inferiority of Rosendale concretes, this Bureau, as 
" well as the Engineering Bureau of the Comptroller's office, has had 
" occasion to make numerous complaints, and the final conclusion was 
" that the practice of using Rosendale cement in concrete foundations 
" for asphalt pavements should be entirely discarded, and that the clause 
" permitting the use of Rosendale cement should be eliminated from the 
" specifications. 

" To our great satisfaction, our recommendation to permit the use of 
" Portland cement exclusively was adopted in the new specifications, 
" published in May, 1899, and in our opinion, consequently, the continu- 
" ous complaints and criticisms made by us in regard to bad concrete 
" foundations appeared to and promised to be a thing of the past. * * '"' 

Copies of said reports of May 4 and October 16, 1899, 
were, by your Honor, transmitted to the Department of 
Highways, and shortly thereafter we were visited by several 
of the cement manufacturers, and the result of these inter- 
views prompted us to send for these samples, and make a 
careful study of the subject of cements. 

Attached to this report will be found Tables Nos. I and 2, 
showing the results we obtained from physical tests, and 
also Table No. 3, showing the results from the chemical 
analyses ; of the thirty-four samples of cement which are the 
subject of the following report (See pages 127, 129 and 131). 

In these tabulated statements the samples are designated 
by a separate series of numbers for each test, for the purpose 
of not disclosing their identity. 



102 

To assure your Honor of the accuracy of the attached 
report and tabulated statements, and to show our behef in 
their scientific importance, we beg to state that we have 
consented to the reading of the report, by the authors, 
before the New York Section of the Society of Chemical 
Industry of England. 

The usual custom of this society being to have all im- 
portant papers that are read before it published in its official 
Journal (which has a large circulation throughout the world) 
we will, upon receipt of same, transmit a copy to your 
Honor. 

We realize the fact that up to the present time, so far as 
we have been able to discover, no correspondence has been 
observed between physical tests and chemical analyses of 
cements. 

This lack of correspondence appeared to us, after the 
thirty-four samples had been analyzed, and, as a consequence, 
we made the method of analysis a subject of investigation, 
and developed a new process of analysis which, upon being 
applied to these thirty-four samples, the physical tests and 
chemical analyses showed corresponding results as to the 
quality of each sample of cement. 

The report, which we herewith submit, will, we believe, 
show beyond a doubt, and demonstrate our finding, that the 
chemical analyses of cements will always confirm the physical 
tests. 

The report also demonstrates the correctness of our pre- 
vious contentions that, in view of the price at which Port- 
land cements can now be bought, Rosendale cements, on 
account of their lack of uniformity, should be entirely elim- 
inated from the specifications in the construction of concrete 
foundations for roadways, where permanence and solidity 
are the first considerations. 



I03 

The importance to this City of this result may be best 
understood by the statement we now make, namely, that if 
called upon by the Corporation Counsel, we are prepared to 
demonstrate the truth of our finding in a court of law. 

We are at present engaged in a still further investigation, 
the results of which will be embodied in a separate report, 
of these same thirty-four samples, to ascertain if optical ex- 
aminations W\\\ confirm the finding herein shown of both the 
physical tests and chemical analyses. 

Respectfully submitted, 

John C. Hertle, 
Edward Owen, 
Commissioners of Accounts. 



104 



REPORT OF 
MESSRS OTTO H* KLEIN and S* R PECKHAM. 



Engineering Bureau, Y 

Office of the Commissioner of Accounts, >- 

New York, May 21, 1900. j 

Subject — Cement Testing. 

Hon, John C. Hertle and Edward Owen, Commissioners 
of Accoimts : 

Gentlemen — The employment of cements in the proper 
construction of foundations for road beds, prompted the 
Department of the Commissioners of Accounts of the City 
of New York to undertake a general examination of the 
most well known cements on this Market. 

For this purpose several of the most prominent manufac- 
turers of cements in the United States, as well as the 
importers of several foreign brands, Avere asked to furnish 
this office with an average sample of their commercial product. 
Thirty-four samples of thirty brands were obtained in this 
way, of which seventeen were Portland cements and thirteen 
were Rosendale or Natural cements. 

All of these samples were tested in the Physical and 
Chemical Laboratories in series of tests, each series being 
carried through by the same person, in order to eliminate as 
far as possible the variations due to personal equation. 

The results thus obtained have been tabulated and are 
shown on the three tables hereto annexed. 



105 

In the Physical Laboratory they were tested according 
to the methods recommended by the Committee on Cement 
Examinations of the American Society of Civil Engineers, 
(Transactions Am. Soc. C. E., Vols. XIII. and XIV.) which 
includes the determination of (i) Average Tensile Strength 
in pounds per square inch ; (2) Fineness; (3) Activity deter- 
mined by Normal Needle, and (4) Faija's Test of Soundness. 



(i) Average Tensile Strength. 

The instrument used was Fairbanks' Automatic Cement 
Testing Machine. 

The determinations were conducted as follows : Three 
different tests were made of each sample, two neat — without 
admixture of any foreign materials — at periods of one and 
seven days, and one with admixture of sand, for a period of 
seven days. The proportion of cement to sand in the mor- 
tar briquettes were for Portland cement, one part of cement 
to three parts of sand and for the natural cement one part 
of cement to two parts of sand. The sand used was crushed 
quartz, commercially known as " No. 3." The method of 
mixing pursued was as follows : The amount of cement in- 
tended for any batch was carefully weighed, placed on a 
glass plate and m.ixed with sufficient water so that after 
having been properly compressed in the mould to remove 
air bubbles, the water could be made to flush the surface. 
By using the trowel properly, the moulds were then turned 
over and the same operation proceeded with on the reverse 
side. The weighing of the cement was by the metric system 
and the water used in mixing (clean hydrant water) was 
measured in a glass cylinder graduated to cubic centimeters, 
the Avater being kept as near as possible at the temperature 
of the air. While the briquettes were allowed to remain in 
the air they were covered with damp blotters. All of the 
briquettes, except those used for the one day tests, were 
allowed to remain in the air twenty-four hours. The one day 



io6 

briquettes were allowed to remain in the air a certain period, 
depending upon their activity. For the natural cements 
this period was one hour and for the Portland cements three 
hours. If they were not thoroughly set in that time they 
were allowed to remain longer in the air. There was one 
extreme case (No. 68 of Table No. i) that set so slowly that it 
was impossible to put the one day briquette in water with- 
out its disintegrating so as to make a test impossible. Con- 
sequently, the results obtained for this cement, for twenty- 
four hours, were obtained from briquettes that were not 
immersed. In the table showing Average Tensile Strength, 
the averages for all briquettes were made from testing; six 
briquettes. The percentage of the water used in mixing 
and the temperature of the same, are the averages of the 
quantities used for the one and seven day neat briquettes. 
The percentages used for mortar briquettes were computed 
on the basis of the entire weight of the mixture of sand and 
cement. 

All of the briquettes were tested on the same Fairbank's 
Automatic Machine, of the latest type, of a capacity of 800 
pounds. The pressure was uniformly applied at the rate of 
425 pounds per minute, as determined by several experi- 
ments. 

Further details could be given, but we deem this informa- 
tion sufficient for the explanation of the tables. 



(2) Fineness. 

To determine the fineness of the samples the percentages 
passing the standard sieves, as described below, were ascer- 
tained. One hundred grams of cement were used for each 
determination. The standard sieves above referred to were 
as follows : No. 50 sieve has twenty-five hundred meshes to 
the square inch and is made of No. 35 Stubb's wire gauge. 
No. 74 sieve has five thousand four hundred and seventy-six 



10/ 

meshes to the square inch and is made of No. 37 wire. Xo. 
100 sieve has ten thousand meshes to the square inch and is 
made of No. 40 wire. 

The Portland Cements were found to be invariably more 
finely ground than the Natural Cements, as will be seen at a 
glance from the table. All the average percentages are con- 
siderably above the usual requirements of fineness. While 
it cannot be denied that fineness is an important factor, an 
inspection of the table show^s that the Portland cements are 
uniformly fine without regard to quality. This quality of 
cements is discussed further on in our paper. 



(3) Activity. 

The activity, or time required for setting, was determined 
by the use of the Vicat apparatus, which may be described 
as follows : A right section of a hollow cone of hard rubber, 
of about seven centimeters average clear diameter and 
four centimeters in height, set on a glass plate, holds 
the cement paste. This cone is placed under a frame 
which supports in a position at right angles with the surface 
of the cement a movable rod, to the lower end of which may 
be attached a piston or needle. The piston has a diameter 
of one centimeter and the needle a cross-section of one square 
millimeter. Suitable weights are attached to the upper part 
of the rod, so that no matter whether either the piston or 
needle may be in use, the weight of the whole movable por- 
tion shall be three hundred grams. There is always attached 
to the rod an index moving over a scale graduated to milli- 
meters and fiftieths of an inch, the scale being fixed on the 
framework. 

All of the cements tested with this apparatus were brought 
to a uniform consistency by mixing with a certain quantity of 
water that the piston, as described, would sink to the base 
through the paste to w^ithin from six to ten millimeters of the 
bottom of the rubber cone, as denoted by the index. 



io8 

The " initial set " was the time that elapsed between the 
mixing and the first moment that the needle did not entirely 
penetrate the paste. The " hard " or " final " set was the 
time that elapsed between the mixing and the moment when 
the paste would support the needle without an appreciable 
impression, which latter, in the case of some of the slow 
setting cements, was sometimes difficult to determine. The 
test above described is largely a comparative one, and is 
used to determine which cement will best fulfill the condi- 
tions under which it may be used. The time of initial set is 
also of importance as representing the limit of time within 
which the cement must be handled or worked. The '' hy- 
draulic activity " is the time that elapsed between the initial 
and final set. The results of this test are shown in the 
table. 



(4) Faija's Test. 

The test for soundness or constancy of volume consists of 
exposing small " pats " of cement, about three inches in 
diameter and of a thickness of about one-half an inch at the 
centre, tapered to very thin edges, and mounted on a glass 
plate, to a moist heat of from 100 degrees to 105 degrees F., 
for six or more hours, until thoroughly set ; they are then 
immersed in a water bath for the remainder of twenty-four 
hours, said bath being kept at a temperature of from 115 
degrees to 120 degrees F., by means of a thermostat. The 
purpose of this test is to impart an artificial age to the 
cement, during the progress of which certain defects are 
made apparent. If the pat adheres to the glass plate and 
does not crack or show any blow-holes the test may be con- 
sidered as satisfactory. 

A new apparatus, constructed by Professor Bauschinger, 
for the determination and measurement of the change of 
volume of cements while setting, has been added to the 
Physical Laboratory of the Commissioners of Accounts, but 



109 

it was not received in time to enable us to apply it to all the 
cements in this list. We propose to give these results at a 
later date. 

We have encountered in our physical tests results which 
have led us to the study of hardened cements in thin sec- 
tions under the microscope. In consequence of the tedious 
detail of this work and also of unexpected delays over which 
we have had no control, we have been unable to present the 
results of this research at this meeting as we expected. 
Without doubt we shall be able to present them with the 
results of other experiments now in progress at an early date 
next year. 

We are confident that a combination of physical, chemical 
and optical tests will ultimately reveal the cause of failure in 
the application of cements, hitherto regarded as obscure and 

difficult of explanation. • 



Chemical Analysis. 

The object of this research was to ascertain how far, if at 
all, the results of the chemical analysis of cement supported 
or confirmed the results obtained in the physical examina- 
tion of cements ; that is to say, the question to be answered 
Avas, What relation, if any, exists between the results obtained 
by physical tests and chemical analysis of cements ? 

On looking up the literature relating to the analysis of 
cements it was found to be in a very unsatisfactory condi- 
tion. There was found to be no agreement as to the pur- 
pose of such analyses. In general it may be said that the 
manner of the analyses described indicates that it is desira- 
ble to set forth the content as consisting of the largest pos- 
sible percentage of lime, siHca and alumina, the latter usually 
including the iron as ferric oxide. Such analyses are wholly 
in the interest of the manufacturers of the cement. 



no 

One of us has had a large experience, several years ago, in 
the analysis of cement and cement clays and limestones. 
None of these materials, however, were used in Portland Ce- 
ments ; they were, strickly speaking, hydraulic lines ; yet the 
problems presented by Portland Cement are practically the 
same, provided an ultimate analysis is sought. The same 
problems were encountered in the analysis of the Estherville 
meteorite, which, at the time it fell, led to a long corre- 
spondence with Dr. J. Lawrence Smith, which his wide 
experience made extremely valuable. All of this experience 
was supplemented by a careful examination of the methods 
described in the last edition of Crooke's Select Methods of 
Chemical Analysis. The result was the practical adoption 
of Stillman's Method of Cement Analysis, as described in 
the Journal of the American Chemical Society for April, 
1893, and March, 1894. 

This scheme is practically as follows : Drying the material 
and weighing out two grammes ; solution in 50 c.c. CHI 
and 5 c.c. HNO3 (presumably concentrated); evaporation 
to dryness; addition of 25 c.c. HCl. (cone?) and ico c.c. of 
H3O, and boiling ; filtering into i^ litre flask and making up 
solution to y^ litre ; analyzing residue by fusion and deter- 
mining silica and alumina ; making 100 c.c. of solution 
alkaline, with NH^HO, warming, filtering and washing, dry- 
ing, igniting and weighing precipitate as Alg O3 + Fco O3 ; 
fusing this precipitate into a silver dish, with KHO, weighing 
the Fe, O3 and determining Alg O3 by difference; adding 
to filtrate (NH4)3C204 in slight excess, setting aside for four 
hours, filtering, washing and determining lime after ignition 
over a blast lamp as CaO. The remainder of the scheme is 
devoted to an unnecessarily intricate determination of mag- 
nesia, sulphuric oxide and the alkalies. 

Some preliminary work led to the planning of a schedule 
that should set forth : the laboratory number, total calcium 
oxide, calcium oxide soluble in water, silica soluble and 
insoluble, aluminum and iron oxides, aluminum oxide soluble 



Ill 

in water, iron as ferric oxide, metallic iron from grinding 
machinery, magnesium oxide, sulphuric oxide which is 
equivalent to sulphate of lime, carbonic acid which is equiva- 
lent to carbonate of lime, loss at a red heat, carbon and 
water. 

From this scheme the alkalies were soon eliminated as 
involving a large amount of labor, practically to no purpose. 
We soon determined that the insoluble portion was not silica ; 
also that concentrated acid was not fit to be used, as it ren- 
dered the silica insoluble ; also that iron from the grinding 
machinery, while present in the sample that we first took up, 
was absent from nearly all the others. It was, therefore, 
eHminated from the scheme. We thereafter soon concluded 
that an ultimate analysis did not reveal differences in very 
unlike cements. Further, on a careful review we found that 
the use of a 20 per cent, solution of HCl was generally recom- 
mended without specifying the manner of its use. 

We then proceeded to weigh out five grammes of the spec- 
imen without drying, as drying often greatly changes the spec- 
imen from the material actually submitted. This was placed 
in a casserole and about 100 c.c. of a 20 per cent, solution of 
HCl was poured upon it. The reaction varied, but was 
usually very vigorous, with evolution of heat sufficient to 
raise the temperature to about 100° C. The insoluble residue 
was filtered off, washed in hot water, dried and ignited as 
"insoluble matter." The solution was then evaporated to 
dryness over a water-bath, the residue dried at 120° C, cooled, 
drenched with concentrated HCl, allowed to stand half an 
hour, diluted with about 200 c.c. of water, filtered, and the 
residue washed with hot water, ignited and weighed as 
" soluble silica.'' The solution was then diluted to one litre 
and equal portions of 100 c.c. were rendered alkaline with 
NH4HO, diluted with water and the ammonia boiled off*. 
The precipitate, consisting of Al^Og and Fe^Og with traces 
of silica, lime and magnesia, was filtered off*, dissolved on the 
filter with diluted HCl, the filter well washed with hot water, 



the acid filtrate carefully precipitated with NH^HO, filtered 
through the same filter, washed, ignited and weighed. A 
trace of silica follows the precipitate, and can only be re- 
moved by putting the dilute acid solution through the filter 
a second time and gathering the alumina and ferric oxide 
on a second filter. The amount of silica, however, is not 
sufficiently large to be of practical importance. 

The filtrate containing the lime was heated to incipient 
boihng and precipitated with an excess of (NH4)2C304, 
allowed to stand over night and next day filtered off and 
ignited over a blast lamp to a constant weight. The mag- 
nesia was precipitated with (NH4)2H,P04 and ignited and 
weighed as pyrophosphate. The filtrate from the magnesium 
was concentrated to about 400 c.c, rendered slightly acid 
with HCl, and while hot precipitated with barium chloride 
and the barium sulphate determined as usual. 

This scheme admits of the determination of the : 

Insoluble residue, 

Soluble silica. 

Alumina and ferric oxides, 

Lime (CaO), 

Magnesia (MgO), 

Sulphuric oxide (SO3). 

It was found that the detemination of the carbonic acid 
involved a large amount of work of questionable, practical 
utility, as, after a number of very careful determinations, it 
was found that the carbonic acid was in every case a small 
percentage less than the amount volatile at a red heat This 
latter determination was made by heating one gram in a 
small covered platinum crucible, at a red heat, to a constant 
weight. 

Carbon was found to be present in several instances in 
appreciable amount. It was determined by passing the 
ori^'-inal acid solution through a balanced filter and deduct- 



113 

ing the weight of the residue after ignition from the weight 
of the dried residue upon the filter. 

Hydrogen sulphide was observed in a few instances 
escaping when the cement was dissolved in dilute acid. 

The percentage of alumina and lime in any given cement 
soluble in water was found to be a varying and significant 
factor. Five grams were in two instances treated with 200 
c.c. of distilled water and immediately filtered. The filtrate 
was acidulated with HCl, this rendered alkaline with 
NH^HO, and after boihng, the precipitated alumina was 
filtered off. The alumina was found to be 0.15 per cent, and 
0.00 per cent. The lime was then precipitated from the 
boiling solution with (NH4)2C204. In the two instances 
under consideration, the percentages of lime were found to be 
1.696 and 1.694. This led to further investigation and the 
conclusion that the 200 c.c. of distilled water were in both 
instances saturated with CaH^O^. Finally i gram of 
cement was treated by bringing it into 500 c.c. of distilled 
water and filtering immediately after thorough stirring. 
The amount of lime was found to vary in the different 
samples from 1.18 per cent, to 8.18 per cent. The alumina 
dissolved varied from 0.00 per cent, to i.ii per cent. 

As soon as the cements were analyzed according to this 
scheme the results were arranged with the physical tests in 
several series, from lowest to highest, in order that any cor- 
respondence between the physical tests and chemical com- 
position might be more apparent. No such correspondence 
was revealed in any case, and the results were apparently 
without relation. 

On arranging the series with reference to the content of 
lime, from low to high, No. 49 appeared as second in the list, 
when in the series arranged upon seven days mortar tests it 
was nearly the last in the list and consequently one of the 
best. No reason was apparent for this striking lack of cor- 
respondence, and the analysis was repeated with carefully 



114 

diluted 20 per cent, acid, into which the cement was slowly- 
jarred. The result appears in the table given below as No. 
II., the first mentioned analysis being No. I. Another 
analysis was made by pouring concentrated acid upon the 
cement, with results given below as No. III. Still another 
was made by pouring upon the cement 10 per cent, acid, 
with still other results given as No. IV. A study of these 
results led to the suggestion that possibly the active chemism 
attending the solution in the several instances observed 
might be responsible for the varying results. 

Five grams were then sifted through a No. 40 sieve upon 
the surface of 250 c. c. of 10 per cent, acid in an 8-inch 
evaporating dish. The mixture was then vigorously stirred 
at intervals for half-an-hour, or until all that would dissolve 
was in solution, when the solution was filtered and the 
residue on the filter thoroughly washed with hot water. 
The results obtained are given as No. V. Assuming that 
the magnesia, sulphuric oxide and loss at a red heat were cor- 
rectly estimated in No. I., Nos. IV. and V. give, respectively, 
a total of 99.20 per cent, and 99.21 per cent. There is very 
little difTerence in the percentages of lime, but the^ sieve 
method yields the largest percentage of soluble silica. It 
was inferred from this result that perhaps a still weaker acid 
might dissolve more silica, and the attempt was made to 
decompose the cement with a 5 per cent, acid, but without 
success. 



Number. 


Insolu- 
ble IN 
HCl. 


I . 


20.42 
7.87 

22.39 
5.83 

5-79 


II 

Ill 


IV 


V 





Solu- 
ble 
Silica. 



12.24 
16.37 
1.63 
17-37 
17.81 



Alumi- 
na AND 
Ferric 
Oxide. 


Lime. 


7-50 


55-05 


8.88 


62.32 


8.98 


62.74 


9.00 


61.76 


8.65 


61.72 



Mag- 
nesia. 



SuL- : Loss 
PHURic lAT Red 
Oxide. Heat. 



2.19 j 1.90 j I. 15 

2.191 1.90 1. 15 

2.19 j 1.90 1. 15 

2.19 1.90 1. 15 

2.19 1.90 I 1. 15 



Lime 
Solu- 
ble IN 
H2O. 


Alumi- 
na Sol- 
uble IN 
H2O. 


5-27 


0.52 


5-27 


0.52 


5.27 


0.52 




0.52 



115 

The series of Portland and Natural Cements were then 
analyzed with ten per cent, acid, using a No. 40 sieve to 
throw them upon the acid in such a manner as to reduce the 
evolution of heat to the lowest terms. The results were 
arranged on the seven-day mortar test, from lowest to 
highest as is shown in Table No. 3. 



. Meaning of Terms. 

There are several terms used in this table that are here 
used, it is believed, for the first time. The required tensile 
strength in pounds for Portland cement is : One day, 160 
pounds; seven days, 350 pounds, and seven days mortar, 125 
pounds — the sum of which is 635 pounds. In computing the 
" total tensile strength in pounds," the tensile strength ob- 
tained in one day and seven days neat and seven days 
mortar tests are added together and are then made a means 
of comparison. By this means of comparison No. 149 is 
found to be of more than twice the required strength. 

The terms " active " and ^' inactive " constituents repre- 
sent, respectively, the active and inert portions of any given 
cement. The percentage of active constituents may be ob- 
tained by adding together the percentages of soluble silica, 
alumina and iron and lime. That of the inactive constituents 
by adding together the percentages of matter "insoluble in 
ten per cent. HCl," of " carbon," when present, of "mag- 
nesia," of '' sulphuric oxide" and of "matter" volatile at a 
red heat. 

The constitution of cements has been under discussion for 
many years, but no results that are final may be said to have 
been reached until those described by the Messrs. Newberry 
were published in 1897. It is not necessary here to review 
the work of Le Chatelier and Vicat. That work has been 
sufficiently well done by the Messrs. Newberry in their 
several papers. We wish, however, to re-state the Newberrys' 
results in order to point out their relation to our own work. 



ii6 

The Newberrys have shown, by the most elaborate and 
conclusive physical and chemical tests, that the formula 
for cements is "% lime = 2.8 (% silica) + i.i (% 
alumina)." They have further shown that in the manu- 
facture of cement, alumina and iron may be taken together, 
while magnesia is inert and sulphuric oxide and the alkalies 
in small quantity may be disregarded. From all of which it 
is fair to conclude that the lime, soluble silica, iron and 
alumina are the constituents of a cement that give it value, 
while all the other constituents that it may contain are inert 
or injurious. 

It may therefore be assumed that a perfect theoretical 
cement, formed synthetically from pure materials, would be 
found upon analysis to be represented by the formula. 



CaO 



2.8 (soluble silica) -f i.i (alumina + iron oxide) 

One, then, becomes the index of the active ingredients of a 
theoretical cement, and the results of analysis may be used 
to express under the above formula the degree of approxi- 
mation obtained in the manufacture of any given cement to 
that theory. This is the significance of the term " active 
index." 

The "inactive index" is obtained by adding together the 
percentages of the inactive constituents with which the 
cement proper is diluted. 

As the Portland and Rosendale Cements are wholly unlike 
substances they will be discussed separately. An examina- 
tion of this table and comparison of the same as to Portland 
Cements with the table of Physical Tests shows, that the first 
five numbers are the same in each table, though differently 
arranged. Four of these five numbers are below the re- 
quired tensile strength on seven days neat and seven days 
mortar tests, the fifth, No. 55, is below on one day neat and 
seven days mortar and barely up to the requirement on 



117 

seven days neat test. On further examination it is observed 
tha^ No. 58 heads all three lists. This is a poor cement all 
through, being low in lime, high in magnesia, with nearly 
one per cent, of carbon, and showing by the loss at the red 
heat of 28.86 per cent, either the effects of ageing or bad or 
insufficient burning. It is a very bad cement. 

No. 55 is a cement high in soluble silica but low in alu- 
mina and iron. It dissolved in dilute HCl with effervescence 
leaving a residue consisting largely of anhydrous ferric oxide. 
This indicates a cement not properly balanced and badly 
burned. It is a poor cement. 

No. 57 is not properly balanced. There is too much in- 
soluble material, and nearly 2 per cent, of carbon, with a 
copious evolution of hydrogen sulphide on solution in dilute 
HCl, With concentrated HCl it completely gelatinized, 
with elimination of COg and H^S. There is not enough 
lime and soluble silica for the alumina. The high inactive 
index of 18.35 P^^ cent, with 0.5 per cent, undetermined 
shows that the substance is really only about four-fifths 
cement. 

Nos. 65 and 66 are too high in soluble silica and too low 
in alumina and iron, with too much magnesia. 

No. 68 is a fairly good cement, but it contains too little 
alumina, too much magnesia, and is the only one in the list 
that contains so much sulphuric oxide as to lead to the sus- 
picion that it has been adulterated with gypsum. 

Nos. 71 and 6y are also fairly good cements. 

Nos. 30 and 53 are two different samples of the same 
brand. Although they are above the required tensile 
strength they are poor cements, either from being under- 
burned or from ageing. As they both contain carbon they 
can reasonably be supposed to be underburned. This re- 
sults in an inactive index in No. 30 of 24.22, and in No. 53 



ii8 

of 18.39. So much inert matter, chiefly carbonate of lime, 
destroys the balance of the active constituents, and while the 
total lime that enters into the active constituents may be 
sufficient to give a proper active index there is only a part 
of such lime in such a condition as to properly combine with 
the silica and alumina and form the hydraulic mixture be- 
longing to them — in other words, a part of the lime is in the 
form of carbonate of lime, and properly belongs in that con- 
dition to the inactive instead of the active constituents. The 
carbonic acid in No. 30 was found to be 12 per cent., which 
is equivalent to 27.276 per cent, of carbonate of lime. The 
15.276 per cent, of lime thus found to be inert, leaves only 
42.884 per cent, in combination with the silica and alumina 
to form about 61 per cent, of the mixture. This explains 
why these cements are so high on seven days neat, and so 
low on seven days mortar tests. 

The remaining seven cements are all, including the slag 
cement, of very superior quality, and these results demon- 
strate to what a high degree of excellence the cement indus- 
try has attained in the United States. Of seventeen samples 
twelve are above test, and of the twelve eight are superior 
to the best foreign cements upon the market. 

From the average composition of the seven best cements 
it can be seen how nearly the manufacturers of American 
Portland Cements approach a theoretically perfect cement. 
The tensile strength is nearly double that which is required, 
and in all higher than the best brands of imported cement. 
The soluble silica is 18.45 P^^ cent., the alumina and ferric 
oxide is 9.46 per cent., the lime is 61.89 P^^ cent. The 
active index is .997. The insoluble material is less than 5 
per cent. ; only a trace of carbon appeared in two of the 
seven specimens, with less than 2 per cent, each of magnesia, 
sulphuric oxide and matter volatile at a red heat — that is to 
say, that the burning is nearly perfect. All of these percent- 
ages give an inactive index of less than 10 per cent., which 
means that the seven best cements examined averaged more 



119 

than 90 per cent, pure, and that this 90 per cent, is almost a 
theoretically perfect cement. 

We think the manufacturers of American Portland 
Cement are to be congratulated. 



RosEXDALE (Natural^ Ce^ients. 

It could not be expected that a cement made by burning 
a natural lime rock containing clay and silica would be found, 
on chemical analysis, to conform in its composition to any 
theoretical formula. The fact that natural cements do not 
could not be more forcibly demonstrated than by an inspec- 
tion of the accompanying table. In general they are badly 
balanced according to Newberry's formula, showing an ex- 
cess of lime over that required for the acid elements, silica, 
alumina and iron. In general also they exhibited the 
effects of both under and over burning. They nearly all 
contained ferric oxide, rendered inactive and insoluble, even 
in concentrated HCl. This condition of the ferric oxide is 
due to overburning. In general they effervesced on solu- 
tion in dilute HCl and lost from 6 per cent, to 15 per cent, 
of matter volatile at a red heat. This reaction indicates 
from 12 per cent, to 30 per cent, of unburned limestone. 
No other results could be expected from careless and 
rapid burning of stone in large lumps in kilns or stacks than 
great lack of uniformity in the result and consequent uncer- 
tainty as to the value of the product. 

At the price at which Portland Cements of the finest qual- 
ity are now placed upon the market very little inducement 
can be ofifered for the use of Natural Cements in construc- 
tions where permanence and solidity are the first con- 
siderations. 



120 



Conclusions. 

The facts hereinbefore stated lead to a number of conclu- 
sions of permanent value. The literature relating to Port- 
land Cements contains references to the supreme importance 
of fine grinding too numerous to mention. A great number 
of experimenters have established the fact that all of the 
material contained in a Portland Cement that is rejected by 
a sieve of lOO meshes to the linear inch possesses very little 
value as cement. It was observed, Avhen jarring the differ- 
ent specimens through a No. 40 sieve, merely for the pur- 
pose of distributing the cement evenly and slowly upon the 
surface of the dilute acid, that all of those cements that con- 
tained CO 2 effervesced more freeh^ as the coarser particles 
were reached, towards the end of the operation. This indi- 
cates that the cement is more easily ground than the un- 
burned carbonate of lime, and that consequently the cement 
contained in the mixture is really found in the finer particles 
while the coarser particles are not cement at all. This fact 
is particularly noticeable in the few cements that contain a 
notable quantity of sand, either fine ground or in grains of 
appreciable size. 

It therefore occurred to us that a proper analysis of a 
Portland Cement should be made only of that portion that 
passed a sieve of 1 00 meshes to the linear inch. Several 
analyses were made in this way, but the results obtained in- 
dicated such radical differences from all recorded analyses 
that the plan was abandoned for the one herein described. 

Mr. Shirmer, in his article published in the March num- 
ber of the Journal of the American Chemical Society for 
1899, advocates the elimination of silica from the portion of 
cement insoluble in acids, by treatment of these residues 
with hydrofluoric acid. His contention is perfectly sound, 
that this insoluble residue should not be determined as silica, 
as it contains lime, alumina and perhaps magnesia. Never- 
theless, it is an insoluble residue, and the silica, lime, alumina 



121 

and magnesia contained therein bear no relation to the silica, 
lime, alumina and magnesia that pass into solution. If the 
analysis is properly conducted it is of no consequence as de- 
termining the value of the cement, of what this residue con- 
sists, so long as it is not soluble in dilute acid, and is not in 
excessive amount. In the cements that we have examined 
this residue usually contains siliceous sand, either fine or 
coarse. In one Portland Cement it consisted largely of 
anhydrous ferric oxide. The cement was under test and 
probably overburned in part. In the natural cements this 
residue consisted in most cases of sand, ferric oxide and 
underburned rock, indicating a very uneven burning. 

Many of the papers which we have examined are inter- 
esting as treating subjects for scientific discussion or informa- 
tion, but do not impress us as of any direct practical value. 
Much of the analytical work set forth or explained in them 
appears to us to be ultimate rather than proximate, and 
as such fails to exhibit those differences of composition in 
detail upon which the differences in value observed among 
cements may be supposed to depend. 

It is not proper, in our judgment, that a cement should 
be dried either at a low or high temperature before analysis 
and therefore deprived of its water or carbonic acid, or both. 
The sample should be analyzed precisely as it is brought to 
the laboratory. The active constituents of a cement are all 
soluble in lo per cent., HCl, when they are properly brought 
together. They are soluble silica, lime, alumina and iron. 
By no method of treatm.ent should either of these be in- 
creased or diminished. In illustration of these statements let 
us further discuss Nos. 30 and 53. The total tensile strength 
indicates a cement from 20 per cent, to 50 per cent, above 
that which is required, as they are both dift'erent specimens 
of the same brand. The active index indicates a consider- 
able excess of lime, but if this large excess had been active 
lime the cement would have been weaker and below test. 
There is a large amount of matter volatile at a red heat, 



122 

some of which would have been expelled and lost in drying. 
Analysis showed 12 per cent of CO^ in No. 30, equivalent 
to 27.276 per cent, of carbonate of lime or unburned lime- 
stone, containing 15.276 per cent, of lime. When this lime 
is subtracted from the total lime — 58.16 per cent. — there 
remains only 42.884 per cent, in combination with the silica, 
alumina and iron, giving an active index of 1.076 and also 
giving 61 per cent, of cem.ent diluted with 39 per cent, of 
carbonate of lime and other inert matter. Such a cement 
would be expected to stand fairly well on a seven days' neat 
test and to nearly or quite fail on a seven days' mortar test. 
The mixture is 61 to 39 to begin with, and when 300 more 
parts of sand are added it becomes 61 to 339, or i to more 
than 5. Such a problem as this is not solved by ultimate 
analysis, with the determination of insoluble silica, lime and 
alumina. 

Before closing this discussion we wish to express our 
unqualified appreciation of the researches carried on by the 
Messrs. Newberry and lately published in the journal of this 
society, Volume 16. It is difficult to place too high a value 
upon researches of this character. They exhibit an absolute 
mastery of the problem, and proceed to conclusions that 
within certain limits are final. These limits are included 
within the more or less complete application of methods of 
verification to which the results are subjected and upon which 
the conclusions are based. That is to say, if the results of a 
perfect theoretical synthesis are tested by perfect physical 
apparatus, confirmed by accurate chemical analysis, such 
tests would furnish an infallible guide in the practical 
manipulation of crude materials ; provided that such prac- 
tical manipulation is always as perfect as the synthesis. 

In the Messrs. Newberry's paper no details are lacking 
concerning the physical tests, while nothing is said concern- 
ing those of the chemical analysis. The steps that lead to 
the declaration, that so much of a clay of a given composi- 
tion plus so much of a pure limestone are required are all 



123 

clearly set forth : but the uncertain element that enters every 
day the practical problem is, to what extent is it possible to 
realize these theoretical conclusions in the working of a 
cement plant ? As a reply to this question we point to the 
best seven American cements, and especially to No. 88. 

It was to determine, first, how far the results of chemical 
analysis would confirm and explain those obtained by phys- 
ical tests ; and, second, how far both would sustain these 
general theoretical conclusions when both are applied to the 
cements on the market, that this research was undertaken. 
We trust our work has not been in vain. 

Respectfully submitted, 

Otto H. Klein, 
S. F. Peckham. 



Tables, 

No. 1. 
No. 2. 
No. 3. 















Compiled and Prepared by the 


12; 

Table No. 1. 

Physical Tests of Thirty-four Samples 
Commissioners of Accounts of The City of New 


OF Cement. 
York, Attached 


to Report Dated May 24. igoo. 





























PORTLAND CEMENTS. 










ROSeBlb (NATURAL) CEMEN IS 










Test of Tensile Strength, for Comparison, 
Te^t of Tensile Strength, for Comparison, 
Test of Tensile Strength, for Comparison, 


one day neat 

seven day neat.... 
seven day morlar {i 


03) 


160 pound 

350 pound 

125 pound 


s per square inch, 
per square inch, 
s per square inch. 




Test of Tensile Strength, for Comparis 
Test of Tensile Strength, for Coraparii 
Test of Tensile Strength, for Comparii 


a.. 


•y nctt. . 


.. 50 pound, per square inch. 
.. 110 pounds per square Inch. 
. 45 I'ounJs per »qu«re inch. 


- - 












.v.„d.yn,orU 


"(•to 2) 




American. 


German. 






American. 










ci^. 




1 






VAaiATIOmiKSAHlBlAND. 


Physlcnl Lftboratorj- Number 


S§ 55 57 


65 6G 


68 71 


67 ** 53 


33 36 52 


49 47 88 


70 


80 1 87 


60 50 50 1 81 1 03 


O-ilol 5. l54| «. 


48 


6- 1«| r. 


•8a 






Tensile Strength in Pound 


per Square Inch. 






Tensile Strength 

IN Pounds 
PER Square Inch. 


Tensile i 


KOTH IN Pounds rsit Squari Inch. 


dav neat lest 


53 
270 
60 


40 
357 
67 


260 
3>' 
98 


'79 
303 
118 


195 
292 
«3S 


253 

527 
■49 


3°1 
482 
150 


376 
645 
■55 


■97 
423 
160 


331 
49 ■ 
167 


267 
700 
206 


256 
739 
209 


3.5 
513 


197 
634 
3'3 


782 
333 


429 
784 
209 

.... 


231 
632 
309 


215 

432 


225 
466 
167 


69 
85 


43 
74 

2$ 

40.5 
75°F 


1 


58 
■34 

33 

36.0 
74='F 


'19 
38 


10* 

40 

.6 

op 


98 
■44 

47 


103 

50 
30.0 

77»F 


lOI 

178 

63 

36.3 
,80, 


69 

32.1 

7J»I' 


9» 
175 

84 


48 
87 

IJJ 
30.0 


aa 

343 
fiO»F 






56 


7. 


30 


Seven Jays one-third sand test 


104 

30 

40.3 
72'>F 


10. 
32 


.,, 


Seven days one-half sand test 




Per cent, water to weight of cement 

Temperature of water used in mixing.. 


75°"' 


74°f 


29-5 
78°F 


24-3 
73°F 


25.1 

74'-F 


23 
74°F 


28.0 
77^ 


19.2 
74''F 


22.3 


25.0 
78=F 


17.0 
6s°F 


20.5 
69OF 


28.5 


^3-7 
78-F 


20.0 
6l<>F 


20.9 
66°F 


22. s 

es-'F 


64<'F 


23.5 
S9»F 


32.8 

75°F 


29.8 


32.1 
74°F 


30.1 


37.0 

73°^ 


28.5 
6a«F 








Percentages Passing Sieve. 










Percentages 
Passing Sieve. 




HuTTACES Passing Siivk. 








Fineness- 
No So sieve 


99 


99 
97 
96 


99 
97 
95 


99 
98 


99 
98 


99 
97 


99 


98 
97 


99 


99 
97 


97 
96 


93 
9' 


99 
98 


99 
97 
96 


98 
94 
92 


99.5 1 .» 
98 \ 99 
96 9S 


90 
86 


99.5 
97 
95 


97 
93 
9" 


99 
96 
95 


94 
83 
Si 


97 
92 
89 


95 
85 
81 






98 
94 

9« 


98 
94 
92 


97 
87 
84 


96 
92 


95 

8s 
83 


87 
84 


96 
85 
83 


96 

85 






Jjl 


8a 












Activity or Neei 


.E Test. 






Activity or 
Needle Test. 




^^nv OR Nuim.K Tkst. 






Aclivily— 

Initialsel 

Final set 


Ih. 
2h.2Sra. 


5 m. 
25 m. 


I h, 


Ih. 
I h. 15 m 


lh.35m 
4h.3S.» 


.l,.45m. 
5h.3om. 


ih.SSni 
3h.30m. 


Ih.iom. 
5h. 




.h.S5m. 
3l'- 


Sh. 


3l>- 
5h. 


ih. 
2h.2Sm. 


2h.30m. 
3h.2Sm. 


3l>- 
6h. 


3h..5m. 
51.. 


4h.40m. 
8h.30m. 


3h.sm. 
6h.3Sm. 


2h.SSm. 
4h.30m. 


iSm. 
30 m. 


3"!. 

13 m. 


5 m. 
iSm. 


Ih. 
Ih.30n.. 


50 m. 
.h.3S.n. 


38 m 
ih.30 


1 


15 m 
.h.asm. 


40 m. 
Ih. 

3fi.« 
73°F 
76°F 


ih.Sm. 
ah. 


ism. 
asm. 

34'4 

Sj"F- 


$501. 
Ih.4om. 




3l>.3S'>'- 
gh.ioin. 


15 m. 
ih-Som. 


Per cent, water 


27. S 

76-^ 
79°F 


27-4 
74°F 
77»F 


35-4 
74-F 
77"F 


28.5 
76°F 
78»F 


32-0 
77"F 
Soop 


27.0 
78<'F 
8l''F 


32.0 
75"F 
79°F 


24.0 
6S"F 
66<>F 




27.0 
77°F 
SlT 


24.0 

es-F 

65»F 


25.0 
7o°F 


29s 
78»F 
79°F 


26.5 
83°F 
84''F 


25.3 
64^ 
66«f 


26.0 
65°F 
7S°F 


28.6 
70°F 
7i°F 


29.0 
67°F 
70»F 


30.0 
62=T 
76<'F 


37.7 
74°F 
75°F 


390 
72'>F 
78°F 


48.0 
74°F 
76»F 


40.0 
65°F 


44.6 
7IOF 
7S°F 


40. < 
64''P| 
66°1 


1 


36.6 
78»F 

8.«r 


43-4 
73''F 
75"F 


44 
74°F 

76"F 


433 
61-F 
07-F 


36.0 


Temperatureof water 

Temperature of air 


(i4°K 
Od'F 








































1 













129 

Table No. 2. 

Summary of 

"Table of Physical Tests of Ti„rty-fouk Sam.'les of Cemekt." 

Compiled and Prepared by the Commissioners of Aecounts of The City of New York, Attached to Report 
dated May 24, 1900. 



PORTLAND CEMENTS. 



ROSENDALE (NATURAL) CEMENTS. 



No. 50 Sieve. 
No. 74 Sieve. 



94 per cent. 
83 " 



99 per 
96 • 





Ac 


riviTY OR Nee 


LE Test. 








Activity— 


5 min. 
25 min. 
IS min. 


3 hrs. 

6llrs. 

3 hrs. 50 min. 


■ hr. 33 min. 
3 hrs. 21 min. 


3 min. 
15 min. 


. l,r. s min. 
SS min. 


31 min. 
59 min. 












24 per cent. 
64" F. 

17.0 per cent. 
61° F. 


35.4 per cent. 
83° F. 
S4=F. 

29.5 per cent. 


25.2 per cent. 
74° F. 
77° F. 

23.3 per cent. 
74° F. 


34.4 per cent. 

64° F. 

66° F. 
29.8 per cent. 

72° F. 


48.0 per cent. 

So= F. 

82«F. 
40.5 per cent. 

78«F. 






73° F. 




75° F. 


Per Cenl. Water used in Briquettes 

Temperature Water used in Briquettes. . . 


34-5 per cent. 
75° F. 



Requirements Expressed in Pounds per Square Inch of Specifications for Tensile Strength 
OF Cements in Use in the Following Cities : 





PORTLAND i ROSENDALE. 


LOCATION. 




San... 


N.„, 


.^?r;. 




One Day. 


S.»e,. Days. 


Seven Days. 


! 

One Day. [ Seven Days. 


L\7s; 




160 


350 
400 

SCO 
375 


125 
■30 
170 
125 


70 1 .SO 
50 1 no 


70 


New York, Department of Highways 

Philadelphia. Department of Public SYorks 


160 

"75 


45 
125 












Table No. 3. 

Chemical Analysis of Thirty-four Samples of Cement. 
Compiled and Prepared by the Commissioners of Accounts of The City of New York, Attached to Report Dated May 24, 1900. 









PORTLAND CEMENTS. 














ROSENDALE (NATURAL) CEMENTS. 




Test of Tensile Strength, for Comparison, one day neat 

Test ot Tensile Strength, for Comparison, seven days n 

Test of Tensile Strength, for Comparison, seven days m 

Total Tensile Strength 










)0Unds per square inch. 
)Ounds per square inch, 
mimrls ner snimri. inch. 










Test of Tensile Strength, for Comparison, one day neat. 






SO pounds per square inch. 
1 10 pounds per square inch. 




at 






■ 350 











3) 






Test of Tensile Strength, for 
Total Tensile St 


r ■ 




■••; " 






• ■ 63s pounds. 


rength 




20s pounds. 


PHYSICAL COMPARISON. 


PHYSICAL COMPARISON. 




Five American Samples 
Below Test. 








Twelve Samples A 


HOVE Tests. 






Two German Samples 
ABOVE Test. 


Four American Samples 
Below Test. 


Eir.iiT American Samim.bs AnovK Test. 


Variations In Same 






E,VEA» 


ERICANS 


..,„..., 


seven IIEST AMERICAN SAMPLES. 




American Samples. 


Physical Laboratorj Nnmljer 


S8 


55 


57 


65 


66 


68 


71 


67 


30 


53 


33 


36 


32 


49 


47 


88 


79" 
Cement. 


Average. 


86 


87 


Average. 


60 

176 


56 


59 1 64 


31 


63 


50 


51 


54 


61 

342 


48 


63 


45 

307 


78 


83a 


Total Tensile Strength in pounds 


383 


464 


669 


600 


625 


929 


933 


1,176 


780 


989 


1,173 


.,.04 


1,060 


1. 144 


r,227 


1,422 


1,172 


1,200 


767 


85S 


813 


«45 


190 182 


216 


225 


465 


289 


300 


447 


35' 


97 


.24 




Ci 


EMICAL COMI'ARIS 


N. 
















Cliemical Lalioratory Nomber 


101 


101 


lOS 


... 


115 


118 


123 


116 


66E 


97 


66G 


79 


96 


93 


85 » 


149 


138 




148 


152 




107 


102 


103 


113 


«6c 


113 


01 


05 


08 


lOS 

7-97 
2.63 
30.70 
1.210 

20.S3 

1.98 
15.42 
36.10 

■-77 


92 


109 

7.11 
6.00 
31.48 
1.187 

21.10 

17.26 
2.47 
15.02 
3.5.85 

2.24 
0.00 


OOn 


00b 


90c 


Active Constituents— 


6.34 

3.22 

39.04 
I.S33 

9-74 
0.856 
11.32 

28.86 
50.7 r« 

0.15 


21.02 

S.7I 

60.41 
0.883 

2.58 

4.20 
6.78 

1.85 


16.09 

9.28 

55-76 

1.000 

8.90 
1.94 

1.69 

1.72 
4.10 

18.35 

2.S1 


19.76 
654 
60.77 
0.971 

4.08 

1.99 

0.72 

12.47 

4.40 
0.68 


19.22 

6.66 

60.72 

1.003 

6.99 

3.30 

2.14 

0.44 

12.87 

2.31 
0.3s 


1S.42 

6.34 

60.76 

1.140 

5.46 

397 
3.18 

2-3' 

14.92 

5.41 


8. 38 
62.75 
1.057 

4-97 

1-33 
1.79 
1.36 
9.45 

5.48 


8. 10 
59.66 
0.973 

5 -03 

2.70 

■■33 

3-39 

12.45 

5-54 


6,23 
58.16 
1.458 

3.8. 
0.27 

0.72 
17.92 
24.22 

2.23 
0.60 


14.83 
7.00 
58.86 
1.196 

2.94 
0.88 

1.04 
12,57 
18.45 

3.16 


17.96 

9-35 

60.06 

0.990 

4-43 
0.00 

1.68 

3.04 

13.43 

8.18 
0.88 


10.76 
63.40 
1.045 

4.04 

0.29 
1.49 
0.97 
6.79 

6.38 


18.26 

59.86 
0.947 

4.42 

0.27 
2.29 
1.62 
8.60 

2.84 


17.41 
8.65 
61.72 
1.039 

5-79 

2.19 

1.90 

1.15 

11.03 

5-27 
0.52 


18.29 

9.00 

60.02 

0.982 

5-35 

4-43 

1.60 

0.63 

12.01 

6.41 
0.78 


J9-43 
8.34 
63.44 
1.005 

3.79 

1-39 
7.07 

6.52 
0.42 


19.61 
9-«3 
63.58 
0.973 

2.16 
2-75 
7.73 

7.18 
0.46 


.8.45 

946 

61.89 

0.997 

4.38 

If! 

1.87 
1.79 

9.83 

6.II 
0.75 


.S.38 

8.98 

60.66 

0.989 

S.05 
0.83 

2.43 

1.32 

12.63 

3.92 


1685 
10.74 
62.13 
1.053 

4.12 

1.64 
0,92 
6.68 

2.29 
0.47 


17.60 

9.86 

61.39 

1.021 

6.10 
) (O0.S3 
1 (f)..one 

11.15 

2.60 
1(1) none 
1(')0 47 


■5.03 

5-35 

34.36 

0.716 

20.91 
}o.oo 

17.92 

S.20 

1.1.03 


16.45 

8.S0 

49. iS 

0.8S3 

14.03 

'•51 

6.04 

21.38 

6.57 


12.03 
7.81 
44 44 
1.065 

14.65 

9.72 

1.62 

11.48 

37.47 

340 


11.74 
5.32 
49.62 
I.2HI 

11.72 
0.6S 
2.63 
1.25 
17.16 
33.41 

4.92 
0.00 


i3S< 

6.20 

31.80 

0.712 

i>>37 

6.60 
49.07 

1.70 


12.0S 

4.94 

36.24 

0.923 

■3'95 

20.27 
2.90 
9.32 

16.44 

6.45 
0.00 


>3.4' 

8.98 

36.30 

0.76.'S 

2497 

1.03 
3-07 

39.19 

3-13 


14.27 

5-43 

34-24 

0.745 

14-34 

■■39 

3-95 

41.69 

2.74 


■3-79 
7.98 
32.28 
0.682 

23.69 

17.69 

1.84 

4-37 

47.50 

1.89 


■3-26 

8-47 

37-72 

0.812 

g.oi 

■ 2.3" 

■-95 

6.03 

29.30 

4.42 
0.26 


15.24 
6.48 
53-76 
1.078 

9-73 
0.72 

■•73 

8.65 

20.83 

5.06 
0.6s 


17.96 

S.42 

56.14 

0.013 




Alumina and Iron Oxides (AU 1 

0,-f-FejOj : \ 

Lime (Ca 0) 


3.03 
42,86 


Active Index 


1.681 


Inactive Constituent?^ 

Insoluble in 10 per cent. HCl 


S.S2 


23.98 
0,54 


Magnesia (MgO) 

Sulphuric Oxide (SO,) 

Volalile at a Red Heat 


■9-^5 


Inactive Index 




Soluble in H.O— 

Lime 




4-88 


Alumina 


= 


== 


o.» 



k 



LIBRARY OF CONGRESS 



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